Apostrophe

The mark ' redirects here. For other uses, see ' (disambiguation)

This article is about the punctuation mark. For other uses, see Apostrophe (disambiguation).

Not to be confused with ʻOkina.

' ’
Apostrophe
U+0027 ' APOSTROPHE U+2019 ’ RIGHT SINGLE QUOTATION MARK
' ’ Typewriter apostrophe or neutral single quote Punctuation apostrophe or typographic right single quote

The apostrophe (' or ’) is a punctuation mark, and sometimes a diacritical mark, in languages that use the Latin alphabet and some other alphabets. In English, the apostrophe is used for three basic purposes:

• The marking of the omission of one or more letters, e.g. the contraction of "do not" to "don't"
• The marking of possessive case of nouns (as in "the eagle's feathers", "in one month's time", "the twins' coats")
• Use as a single quotation mark

It is also used in a few distinctive cases for the marking of plurals, e.g. "p's and q's" or Oakland A's.

It is also used informally to indicate the units of foot and minutes of arc, although in these uses, the prime symbol is generally preferred.

The word apostrophe comes from the Greek ἡ ἀπόστροφος [προσῳδία], through Latin and French.

==Usage in Englishbanna big booty

Non-English use

As a mark of elision

In many languages, especially European languages, the apostrophe is used to indicate the elision of one or more sounds, as in English.

• In Albanian, the apostrophe is used to show that a vowel has been omitted from words, especially in different forms of verbs and in some forms of personal pronoun. For example, t'i: them (from të + i: them), m'i mori (from më + i mori). It is used too in some of the forms of possessive pronouns, for example: s'ëmës (from së ëmës).
• In Afrikaans, as in Dutch, the apostrophe is used to show that letters have been omitted from words. The most common use is in the indefinite article 'n, which is a contraction of een meaning 'one' (the number). As the initial e is omitted and cannot be capitalised, the second word in a sentence that begins with 'n is capitalised instead. For example: 'n Boom is groen, 'A tree is green'. In addition, the apostrophe is used for plurals and diminutives where the root ends with long vowels, e.g. foto's, taxi's, Lulu's, Lulu'tjie, etc.
• In Catalan, French, Italian, Ligurian, and Occitan word sequences such as (coup) d'état, (maître) d'hôtel (often shortened to maître d', when used in English), L'Aquila, L'Alpe d'Huez and L'Hospitalet de Llobregat the final vowel in the first word (de 'of', le 'the', etc.) is elided because the word that follows it starts with a vowel or a mute h. French elision similarly occurs with qu'il instead of que il ('that he'), c'est instead of ce est ('it is' / 'it's'), and so on. Catalan, French, Italian, and Occitan surnames sometimes contain apostrophes of elision, e.g. d’Alembert, D'Angelo.
  • French feminine singular possessive adjectives do not undergo such elision anymore, but change to the masculine form instead: ma preceding église becomes mon église ('my church').
  • Quebec's Bill 101, which dictates the use of French in the province, prohibits the use of apostrophes in proper names in which it would not be used in proper French (thus the international donut chain Tim Hortons, originally spelled with the possessive apostrophe as Tim Horton's, was required to drop the apostrophe in Quebec to comply with Bill 101).
• In Danish, apostrophes are sometimes seen on commercial materials. One might commonly see Ta' mig med ('Take me with [you]') next to a stand with advertisement leaflets; that would be written Tag mig med in standard orthography. As in German, the apostrophe must not be used to indicate the possessive, except when there is already an s, x or z present in the base form, as in Esajas' bog ('the Book of Esajas').
• In Dutch, as in Afrikaans, the apostrophe is used to indicate omitted characters. For example, the indefinite article een can be shortened to 'n, and the definite article het shortened to 't. When this happens in the first word of a sentence, the second word of the sentence is capitalised. In general, this way of using the apostrophe is considered non-standard, except as genitivus temporalis in 's morgens, 's middags, 's avonds, 's nachts (for des morgens, des middags, des avonds, des nachts, 'at morning, at afternoon, at evening, at night') and in some frozen place names such as 's-Hertogenbosch (possessive, lit. "The Duke's forest"), 's-Gravenhage (traditional name of The Hague, lit. "The Count's hedge"), 's-Gravenbrakel (Braine-le-Comte, in Belgium), 's-Hertogenrade (Herzogenrath, in Germany), etc. In addition, the apostrophe is used for plurals where the singulars end with long vowels, e.g. foto's, taxi's; and for the genitive of proper names ending with these vowels, e.g. Anna's, Otto's. These are in fact elided vowels; use of the apostrophe prevents spellings like fotoos and Annaas. However, most diminutives do not use an apostrophe where the plural forms would; producing spellings such as fotootje and taxietje.
• In Esperanto, the Fundamento limits the elision mark to the definite article l' (from la) and singular nominative nouns (kor' from koro, 'heart'). This is mostly confined to poetry and songs. Idiomatic phrases such as dank' al (from (kun) danko al, 'thanks to') and del' (from de la 'of the') are nonetheless frequent. In-word elision is usually marked with a hyphen, as in D-ro (from doktoro, 'Dr'). Some early guides used and advocated the use of apostrophes between word parts, to aid recognition of such compound words as gitar'ist'o, 'guitarist'; but in the latter case, modern usage is to use either a hyphen or a middle dot when disambiguation is necessary, as in ĉas-hundo or ĉas·hundo, "a hunting dog", not to be mispronounced as ĉa.ŝun.do.
• In Finnish, the apostrophe is used in inflected forms of words whose basic form has a "k" between similar vowels, to show that the "k" has elided in the inflected form: for example the word raaka ("raw") becomes raa'at in the plural. The apostrophe shows that the identical vowels on either side of it belong to different syllables.
• The Galician language standard admits the use of the apostrophe (apóstrofo) for contractions that normally do not use it (e.g.: de + a= da), when the second element begins a proper noun, generally a title: o argumento d'A Esmorga (the plot of A Esmorga [title of a novel]). They are also used to reproduce oral elisions and, as stated below, to join (or split) commercial names of popular public establishments such as restaurants (O'Pote, The pot).
• In Ganda, when a word ending with a vowel is followed by a word beginning with a vowel, the final vowel of the first word is elided and the initial vowel of the second word lengthened in compensation. When the first word is a monosyllable, this elision is represented in the orthography with an apostrophe: in taata w'abaana 'the father of the children', wa ('of') becomes w'; in y'ani? ('who is it?'), ye ('who') becomes y'. But the final vowel of a polysyllable is always written, even if it is elided in speech: omusajja oyo ('this man'), not *omusajj'oyo, because omusajja ('man') is a polysyllable.
• In German an apostrophe is used almost exclusively to indicate omitted letters. It must not be used for plurals or most of the possessive forms. The only exceptions are the possessive cases of names ending in an "s"-sound as in Max' Vater, or "to prevent ambiguities" in all other possessive cases of names, as in Andrea's Blumenladen (referring to the female name Andrea, not the male name Andreas). The English/Saxon style of using an apostrophe for possession was introduced after the spelling reform, but is strongly disagreed on by native speakers, and discouraged. Although possessive usage (beyond the exceptions) is widespread, it is often deemed incorrect. The German equivalent of "greengrocers' apostrophes" would be the derogatory Deppenapostroph ('idiot's apostrophe'; see the article Apostrophitis in German Wikipedia).
• In modern printings of Ancient Greek, apostrophes are also used to mark elision. Some Ancient Greek words that end in short vowels elide when the next word starts with a vowel. For example, many Ancient Greek authors would write δἄλλος (d'állos) for δὲ ἄλλος (dè állos) and ἆροὐ (âr' ou) for ἆρα οὐ (âra ou). Such modern usage should be carefully distinguished from polytonic Greek's native rough and smooth breathing marks, which usually appear as a form of rounded apostrophe.
• In Hebrew, the geresh (׳), often typed as an apostrophe, is used to denote abbreviations. A double geresh (״), known by the dual form gershayim, is used to denote acronyms or initialisms; it is inserted before (i.e., to the right of) the last letter of the acronym. Examples: פרופ׳ (abbreviation for פרופסור, 'professor', 'professor'); נ״ב (nun-bet, 'P.S.'). The geresh is also used to indicate the elision of a sound; however, this use is much less frequent, and confined to the purpose of imitating a natural, informal utterance, for example: אנ׳לא (anlo – short for אני לא, ani lo, 'I am/do not').
• In Irish, the past tense of verbs beginning with a vowel, or with fh followed by a vowel, begins with d' (elision of do), for example do oscail becomes d'oscail ('opened') and do fhill becomes d'fhill ('returned'). The copula is is often elided to 's, and do ('to'), mo ('my') etc. are elided before f and vowels.
• In Italian it is used for elision with pronouns, as in l'ha instead of la ha; with articles, as in l'opera instead of la opera; and for truncation, as in po' instead of poco. Stylistically, sentences beginning with È (as in È vero che ...) are often rendered as E' in newspapers, to minimise leading (inter-line spacing).
• In modern Norwegian, the apostrophe marks that a word has been contracted, such as ha'kke from har ikke ('have/has not'). Unlike English and French, such elisions are not accepted as part of standard orthography but are used to create a more "oral style" in writing. The apostrophe is also used to mark the genitive for words that end in an -s sound: words ending in -s, -x, and -z, some speakers also including words ending in the sound [ʂ]. As Norwegian does not form the plural with -s, there is no need to distinguish between an -s forming the possessive and the -s forming the plural. Therefore, we have mann ('man') and manns ('man's'), without apostrophe, but los ('naval pilot') and los' ('naval pilot's'). Indicating the possessive for the two former American presidents named George Bush, whose names end in [ʂ], could be written as both Bushs (simply adding an -s to the name) and Bush' (adding an apostrophe to the end of the name).
• In Portuguese the apostrophe is used to reproduce certain popular pronunciations such as s'enxerga (pay attention to yourself) or in a few combinations of word, when there is the suppression of the vowel of the preposition de in certain compound words (the ones formed by two or more stems) such as caixa-d'água ('water tower'), galinha-d'angola ('guineafowl'), pau-d'alho (a plant species, Gallesia integrifolia), estrela-d'alva ('morning star'), etc. Portuguese has many contractions between prepositions and articles or pronouns (like na for em + a), but these are written without an apostrophe. Also, the apostrophe is most commonly not used in the word pra, the reduced or popular form of the preposition para (but some advocate for its used in preposition + article contractions: para + a = p'ra/pra, para + o = p'ro/pro, etc.).
• Modern Spanish no longer uses the apostrophe to indicate elision in standard writing, although it can sometimes be found in older poetry for that purpose. Instead Spanish writes out the spoken elision in full (de enero, mi hijo) except for the contraction del for de + el, and al for a + el, which use no apostrophe.
• In Swedish, the apostrophe marks an elision, such as på sta'n, short for på staden ('in the city'), to make the text more similar to the spoken language. This is relaxed style, fairly rarely used, and would not be used by traditional newspapers in political articles, but could be used in entertainment related articles and similar. The formal way to denote elision in Swedish is by using colon, e.g. S:t Erik for Sankt Erik which is rarely spelled out in full. The apostrophe must not be used to indicate the possessive except – although not mandatory – when there is already an s, x or z present in the base form, as in Lukas' bok.
• Welsh uses the apostrophe to mark elision of the definite article yr ('the') following a vowel (a, e, i, o, u, y, or, in Welsh, w), as in i'r tŷ, 'to the house'. It is also used with the particle yn, such as with mae hi'n, 'she is'.

As a glottal stop

See also: ʻOkina, Saltillo (linguistics), Modifier letter apostrophe, Modifier letter double apostrophe, and Modifier letter right half ring

Several languages and transliteration systems use the apostrophe or some similar mark to indicate a glottal stop, sometimes considering it a letter of the alphabet:

• In several Finno-Ugric languages, such as Estonian and Finnish; for example in the Finnish word raa’an, being the genitive or accusative of raaka ('raw').
• In Guarani, it is called puso /puˈso/, and used in the words ñe'ẽ (language, to speak), ka'a (grass), a'ỹ (sterile).
• In Hawaiian, the ʻokina ⟨ʻ⟩, an inverted apostrophe, is often rendered as ⟨'⟩. It is considered a letter of the alphabet.
• Mayan.
• In the Tongan language, the apostrophe is called a fakauʻa and is the last letter of the alphabet. It represents the glottal stop. Like the ʻokina, it is inverted.
• Various other Austronesian languages, such as Samoan, Tahitian, and Chamorro.
• Tetum, one of the official languages of East Timor.
• The Brazilian native Tupi language.
• Mossi (Mooré), a language of Burkina Faso.
• In Võro, the apostrophe is used in parallel with the letter q as symbol of plural, for example majaq or maja' ('houses'), imperative annaq or anna', and in all other word forms with glottal stop.
• Several fictional languages such as Klingon, D'ni, Mando'a or Na'vi add apostrophes to make names appear "alien".

The apostrophe represents sounds resembling the glottal stop in the Turkic languages and in some romanizations of Semitic languages, including Arabic and Hebrew. In that case, the letter 'ayn (Arabic ع and Hebrew ע) is correspondingly transliterated with the opening single quotation mark.

As a mark of palatalization or non-palatalization

Some languages and transliteration systems use the apostrophe to mark the presence, or the lack of, palatalization:

• In Belarusian and Ukrainian, the apostrophe is used between a consonant and a following "soft" (iotated) vowel (Be.: е, ё, ю, я; Uk.: є, ї, ю, я) to indicate that no palatalization of the preceding consonant takes place, and the vowel is pronounced in the same way as at the beginning of a word. It therefore marks a morpheme boundary before /j/ and, in Belarusian, is a letter of the alphabet (as the hard sign in Russian is) rather than a simple punctuation mark in English, as it is not a punctuation mark in Belarusian. It appears frequently in Ukrainian, as, for instance, in the words: ⟨п'ять⟩ (p"jat') 'five', ⟨від'їзд⟩ (vid"jizd) 'departure', ⟨об'єднаний⟩ (ob"jednanyj) 'united', ⟨з'ясувати⟩ (z"jasuvaty) 'to clear up, explain', ⟨п'єса⟩ (p"jesa) play (drama), etc.
• In Russian and some derived alphabets, the same function has been served by the hard sign (ъ, formerly called yer). But the apostrophe saw some use as a substitute after 1918, when Soviet authorities enforced an orthographic reform by confiscating movable type bearing the hard sign from stubborn printing houses in Petrograd.
• In some Latin transliterations of certain Cyrillic alphabets (for Belarusian, Russian, and Ukrainian), the apostrophe is used to replace the soft sign (ь, indicating palatalization of the preceding consonant), e.g., Русь is transliterated Rus' according to the BGN/PCGN system. (The prime symbol is also used for the same purpose.) Some of these transliteration schemes use a double apostrophe ( ˮ ) to represent the apostrophe in Ukrainian and Belarusian text and the hard sign (ъ) in Russian text, e.g. Ukrainian слов'янське ('Slavic') is transliterated as slov"jans'ke.
• Some Karelian orthographies use an apostrophe to indicate palatalization, e.g. n'evvuo ('to give advice'), d'uuri ('just (like)'), el'vüttiä ('to revive').
• In Võro an apostrophe is often (also in the Võro Wikipedia) used as a simplification to replace the regular Võro palatalization mark which is the accute accent, for example as'aq replacing regular form aśaq ('things').

To separate morphemes

Some languages use the apostrophe to separate the root of a word and its affixes, especially if the root is foreign and unassimilated. (For another kind of morphemic separation see pinyin, below.)

• In Danish an apostrophe is sometimes used to join the enclitic definite article to words of foreign origin, or to other words that would otherwise look awkward. For example, one would write IP'en to mean "the IP address". There is some variation in what is considered "awkward enough" to warrant an apostrophe; for instance, long-established words such as firma ('company') or niveau ('level') might be written firma'et and niveau'et, but will generally be seen without an apostrophe. Due to Danish influence, this usage of the apostrophe can also be seen in Norwegian, but is non-standard – a hyphen should be used instead: e.g. CD-en (the CD).
• In Estonian, apostrophes can be used in the declension of some foreign names to separate the stem from any declension endings; e.g., Monet' (genitive case) or Monet'sse (illative case) of Monet (name of the famous painter).
• In Finnish, apostrophes are used in the declension of foreign names or loan words that end in a consonant when written but are pronounced with a vowel ending, e.g. show'ssa ('in a show'), Bordeaux'hon ('to Bordeaux'). For Finnish as well as Swedish, there is a closely related use of the colon.
• In Polish, the apostrophe is used exclusively for marking inflections of words and word-like elements (but not acronyms – a hyphen is used instead) whose spelling conflicts with the normal rules of inflection. This mainly affects foreign words and names. For instance, one would correctly write Kampania Ala Gore'a for "Al Gore's campaign". In this example, Ala is spelled without an apostrophe, since its spelling and pronunciation fit into normal Polish rules; but Gore'a needs the apostrophe, because e disappears from the pronunciation, changing the inflection pattern. This rule is often misunderstood as calling for an apostrophe after all foreign words, regardless of their pronunciation, yielding the incorrect Kampania Al'a Gore'a, for example. The effect is akin to the greengrocers' apostrophe (see above).
• In Turkish, proper nouns are capitalised and an apostrophe is inserted between the noun and any following inflectional suffix, e.g. İstanbul'da ("in Istanbul"), contrasting with okulda ("in school", okul is a common noun) and İstanbullu ('Istanbulite', -lu is a derivational suffix).
• In Welsh the apostrophe is used with infixed pronouns in order to distinguish them from the preceding word (e.g. a'm chwaer, 'and my sister' as opposed to am chwaer, 'about a sister').

Miscellaneous uses in other languages

• In Breton, the combination cʼh is used for the consonant /x/ (like ch in Scottish English Loch Ness), while ch is used for the consonant /ʃ/ (as in French chat or English she).
• In Czech, an apostrophe is used for writing to indicate spoken or informal language where the writer wants to express the natural way of informal speech, but it should not be used in formal text or text of a serious nature. E.g., instead of četl ('he read'), the word form čet' is used. Čet' is the informal variant of the verb form četl, at least in some varieties. These two words are the same in meaning, but to use the informal form gives the text a more natural tone, as though a friend were talking to you. Furthermore, the same as in the Slovak case below holds for lowercase t and d, and for the two-digit year notation.
• In Finnish, one of the consonant gradation patterns is the change of a k into a hiatus, e.g. keko → keon ('a pile' → 'a pile's'). This hiatus has to be indicated in spelling with an apostrophe if a long vowel (represented by doubling (e.g. oo) or the final vowel of a diphthong (e.g. uo) would be immediately followed by the same vowel, e.g. ruoko → ruo'on, vaaka → vaa'an. (This is in contrast to compound words, where the problem of a vowel recurring over a syllable break is solved with a hyphen, e.g. maa-ala, 'land area'.) Similarly, the apostrophe is used to mark the hiatus (contraction) that occurs in poetry, e.g. miss' on for missä on ('where is').
• Galician restaurants sometimes use ' in their names following the standard article O ('the').
• In Ganda, ng' (pronounced /ŋ/) is used in place of ŋ on keyboards where this character is not available. The apostrophe distinguishes it from the letter combination ng (pronounced [ŋɡ]), which has separate use in the language. Compare this with the Swahili usage below.
• In Hebrew, the geresh (a diacritic similar to the apostrophe and often represented by one) is used for several purposes other than to mark an elision:
  • As an adjacent to letters to show sounds that are not represented in the Hebrew alphabet: Sounds such as /dʒ/ (English j as in job), /θ/ (English th as in thigh), and /tʃ/ (English ch as in check) are indicated using ג, ת, and צ with a geresh (informally chupchik). For example, the name George is spelled ג׳ורג׳ in Hebrew (with ג׳ representing the first and last consonants).
  • To denote a Hebrew numeral (e.g., נ׳, which stands for '50')
  • To denote a Hebrew letter which stands for itself (e.g., מ׳ – the letter mem)
  • Gershayim (a double geresh) to denote a Hebrew letter name (e.g., למ״ד – the letter lamed)
  • Another (rarer) use of geresh is to denote the last syllable (which in some cases, but not all, is a suffix) in some words of Yiddish origin (e.g., חבר׳ה, מיידל׳ה).
  • In the Middle Ages and the Early modern period, gershayim were also used to denote foreign words, as well as a means of emphasis.
• In Italian, an apostrophe is sometimes used as a substitute for a grave or an acute accent. This may be done after an initial E or an accented final vowel (when writing in all-capitals), or when the proper form of the letter is unavailable for technical reasons. So a sentence beginning È vero che ... ('It is true that...') may be written as E' vero che .... This form is often seen in newspapers, as it is the only case of an accent above the cap height and its omission permits the text to be more closely spaced (leading). Less commonly, a forename like Niccolò might be rendered as Niccolo', or NICCOLO'; perché, as perche', or PERCHE'. This applies only to machine or computer writing, in the absence of a suitable keyboard.
• In Jèrriais, one of the uses of the apostrophe is to mark gemination, or consonant length: For example, t't represents /tː/, s's /sː/, n'n /nː/, th'th /ðː/, and ch'ch /ʃː/ (contrasted with /t/, /s/, /n/, /ð/, and /ʃ/).
• In Lithuanian, the apostrophe is occasionally used to add a Lithuanized ending on an international word, e.g.- "parking'as", "Skype'as", "Facebook'as".
• In standard Lojban orthography, the apostrophe is a letter in its own right (called y'y [əhə]) that can appear only between two vowels, and is phonemically realised as either [h] or, more rarely, [θ].
• In Macedonian the apostrophe is sometimes used to represent the sound schwa, which can be found on dialectal levels, but not in the Standard Macedonian.
• In Slovak, the caron over lowercase t, d, l, and uppercase L consonants resembles an apostrophe, for example, ď, ť, ľ, and Ľ. This is especially so in certain common typographic renderings. But it is non-standard to use an apostrophe instead of the caron. There is also l with an acute accent: ĺ, Ĺ. In Slovak the apostrophe is properly used only to indicate elision in certain words (tys', as an abbreviated form of ty si ('you are'), or hor' for hore ('up')); however, these elisions are restricted to poetry (with a few exceptions). Moreover, the apostrophe is also used before a two-digit year number (to indicate the omission of the first two digits): '87 (usually used for 1987).
• In Swahili, an apostrophe after ng shows that there is no sound of /ɡ/ after the /ŋ/ sound; that is, that the ng is pronounced as in English singer, not as in English finger.
• In Switzerland, the apostrophe is used as thousands separator alongside the fixed space (e.g., 2'000'000 or 2000000 for two million) in all four national languages.
• In the new Uzbek Latin alphabet adopted in 2000, the apostrophe serves as a diacritical mark to distinguish different phonemes written with the same letter: it differentiates o' (corresponding to Cyrillic ў) from o, and g' (Cyrillic ғ) from g. This avoids the use of special characters, allowing Uzbek to be typed with ease in ordinary ASCII on any Latin keyboard. In addition, a postvocalic apostrophe in Uzbek represents the glottal stop phoneme derived from Arabic hamzah or 'ayn, replacing Cyrillic ъ.
• In English Yorkshire dialect, the apostrophe is used to represent the word the, which is contracted to a more glottal (or 'unreleased') /t/ sound. Most users will write in t'barn ('in the barn'), on t'step ('on the step'); and those unfamiliar with Yorkshire speech will often make these sound like intuh barn and ontuh step. A more accurate rendition might be in't barn and on't step, though even this does not truly convey correct Yorkshire pronunciation as the t is more like a glottal stop.
• In the pinyin (hànyǔ pīnyīn) system of romanization for Standard Chinese, an apostrophe is often loosely said to separate syllables in a word where ambiguity could arise. Example: the standard romanization for the name of the city Xī'ān includes an apostrophe to distinguish it from a single-syllable word xian. More strictly, however, it is standard to place an apostrophe only before every a, e, or o that starts a new syllable after the first if it is not preceded by a hyphen or a dash. Examples: Tiān'ānmén, Yǎ'ān; but simply Jǐnán, in which the syllables are ji and nan, since the absence of an apostrophe shows that the syllables are not jin and an (contrast Jīn'ān). This is a kind of morpheme-separation marking (see above).
• In the largely superseded Wade–Giles romanization for Standard Chinese, an apostrophe marks aspiration of the preceding consonant sound. Example: in tsê (pinyin ze) the consonant represented by ts is unaspirated, but in ts'ê (pinyin ce) the consonant represented by ts' is aspirated. Some academic users of the system write this character as a spiritus asper (ʽ or ʻ) or single left (opening) quotation mark (‘).
• In some systems of romanization for the Japanese, the apostrophe is used between moras in ambiguous situations, to differentiate between, for example, na and n + a. (This is similar to the practice in Pinyin mentioned above.)
• In science fiction and fantasy, the apostrophe is often used in fictional names, sometimes to indicate a glottal stop (for example Mitth'raw'nuruodo in Star Wars), but also sometimes simply for decoration.

Typographic form

Typographic (green) and typewriter (red) apostrophe, followed by a prime (blue), between letters Í and í (using acute accent), using the fonts: Arial, Calibri, Tahoma, Times New Roman, and Linux Libertine

The shape of the apostrophe originated in manuscript writing, as a point with a downwards tail curving clockwise. This form was inherited by the typographic apostrophe, ’, also known as the typeset apostrophe (or, informally, the curly apostrophe). Later sans-serif typefaces had stylised apostrophes with a more geometric or simplified form, but usually retaining the same directional bias as a closing quotation mark.

With the invention of the typewriter, a "neutral" or "straight" shape quotation mark, ', was created to represent a number of different glyphs with a single keystroke: the apostrophe, both the opening and the closing single quotation marks, the single primes, and on some typewriters even the exclamation point (by backspacing and overprinting with a period). This is known as the typewriter apostrophe or vertical apostrophe. The same convention was adopted for double quotation marks ("). Both simplifications carried over to computer keyboards and the ASCII character set.

Informal use in measurement and mathematics

Further information: Prime (symbol)

Formally, the symbol used to represent a foot of length, depth, or height, is ′ (prime) and that for the inch is ″ (double prime). (Thus, for example, the notation 5′ 7″ signifies 5 feet and 7 inches). Similarly, the prime symbol is the formal representation of a minute of arc (1/60 of a degree in geometry and geomatics), and double prime represents a second of arc (for example, 17°54′32″ represents 17 degrees 54 minutes and 32 seconds). Similarly in mathematics, the prime is generally used to generate more variable names for similar things without resorting to subscripts, with x′ generally meaning something related to (or derived from) x.

Because of the very close similarity of the typewriter apostrophe and typewriter double quote to prime and double prime, substitution in informal contexts is ubiquitous but they are deprecated in contexts where proper typography is important. There is also a risk of an automatic process "correcting" a typewriter apostrophe to a typographic apostrophe, which results in another variant when a prime symbol was intended.

Unicode

In its Unicode Standard (version 13.0), the Unicode Consortium describes three characters that represent apostrophe:

• U+0027 ' APOSTROPHE: The typewriter or ASCII apostrophe. The standard remarks:

For historical reasons, U+0027 is a particularly overloaded character. In ASCII, it is used to represent a punctuation mark (such as right single quotation mark, left single quotation mark, apostrophe punctuation, vertical line, or prime) or a modifier letter (such as apostrophe modifier or acute accent). Punctuation marks generally break words; modifier letters generally are considered part of a word.

• U+2019 ’ RIGHT SINGLE QUOTATION MARK is preferred where the character is to represent a punctuation mark, as for contractions: "we’ve", and the code is also referred to as a punctuation apostrophe. The closing single quote and the apostrophe were unified in Unicode 2.1 "to correct problems in the mapping tables from Windows and Macintosh code pages." This can make searching text more difficult as quotes and apostrophes cannot be distinguished without context.
• U+02BC ʼ MODIFIER LETTER APOSTROPHE (from Unicode block Spacing Modifier Letters) is preferred where the apostrophe is to represent a modifier letter (for example, in transliterations to indicate a glottal stop). In the latter case, it is also referred to as a letter apostrophe. The letter apostrophe may be used, for example, in transliterations to represent the Arabic glottal stop (hamza) or the Cyrillic "soft sign", or in some orthographies such as cʼh of Breton, where this combination is an independent trigraph. ICANN considers this the proper character for Ukrainian apostrophe within IDNs. This character is rendered identically to U+2019 in the Unicode code charts, and the standard cautions that one should never assume this code is used in any language.

Characters similar to apostrophe

• U+0027 ' APOSTROPHE
• U+0060 ` GRAVE ACCENT
• U+00B4 ´ ACUTE ACCENT
• U+02B9 ʹ MODIFIER LETTER PRIME
• U+02BB ʻ MODIFIER LETTER TURNED COMMA Hawaiian ʻokina and for the transliteration of Arabic and Hebrew ʻayn.
• U+02BC ʼ MODIFIER LETTER APOSTROPHE
• U+02BD ʽ MODIFIER LETTER REVERSED COMMA
• U+02BE ʾ MODIFIER LETTER RIGHT HALF RING Arabic hamza and Hebrew alef.
• U+02BF ʿ MODIFIER LETTER LEFT HALF RING Arabic and Hebrew ʿayin.
• U+02C8 ˈ MODIFIER LETTER VERTICAL LINE Stress accent or dynamic accent.
• U+02CA ˊ MODIFIER LETTER ACUTE ACCENT
• U+02EE ˮ MODIFIER LETTER DOUBLE APOSTROPHE One of two characters for glottal stop in Nenets.
• U+0301 ◌́ COMBINING ACUTE ACCENT
• U+0313 ◌̓ COMBINING COMMA ABOVE Also known as combining Greek psili.
• U+0314 ◌̔ COMBINING REVERSED COMMA ABOVE Also known as combining Greek dasia.
• U+0315 ◌̕ COMBINING COMMA ABOVE RIGHT
• U+0341 ◌́ COMBINING ACUTE TONE MARK
• U+0343 ◌̓ COMBINING GREEK KORONIS Identical to U+0313.
• U+0374 ʹ GREEK NUMERAL SIGN Also known as Greek dexia keraia.
• U+0384 ΄ GREEK TONOS
• U+055A ՚ ARMENIAN APOSTROPHE
• U+059C ֜ HEBREW ACCENT GERESH
• U+059D ֝ HEBREW ACCENT GERESH MUQDAM
• U+05F3 ׳ HEBREW PUNCTUATION GERESH
• U+1FBD ᾽ GREEK KORONIS
• U+1FBF ᾿ GREEK PSILI
• U+2018 ‘ LEFT SINGLE QUOTATION MARK (or turned comma, which can mark a letter's omission)
• U+2019 ’ RIGHT SINGLE QUOTATION MARK
• U+201B ‛ SINGLE HIGH-REVERSED-9 QUOTATION MARK
• U+2032 ′ PRIME
• U+2035 ‵ REVERSED PRIME
• U+A78B Ꞌ LATIN CAPITAL LETTER SALTILLO Saltillo of the languages of Mexico.
• U+A78C ꞌ LATIN SMALL LETTER SALTILLO
• U+FF07 ＇ FULLWIDTH APOSTROPHE Fullwidth form of the typewriter apostrophe.

Computing

In modern computing practice, Unicode is the standard and default method for character encoding. However, Unicode itself and many legacy applications have echoes of earlier practices. Furthermore, the limited character set provided by computer keyboards has also required practical and pragmatic adjustments. These issues are detailed below.

ASCII encoding

The typewriter apostrophe, ', was inherited by computer keyboards, and is the only apostrophe character available in the (7-bit) ASCII character encoding, at code value 0x27 (39). In ASCII, it may be used to represent any of left single quotation mark, right single quotation mark, apostrophe, vertical line or prime (punctuation marks), or an acute accent (modifier letters).

Many earlier (pre-1985) computer displays and printers rendered the ASCII apostrophe as a typographic apostrophe, and rendered the backtick (freestanding grave accent symbol, `, 0x60, 96) as a matching left single quotation mark. This allowed a more typographic appearance of text: ``I can't'' would appear as ``I can´t´´ on these systems. This can still be seen in many documents prepared at that time, and is still used in the TeX typesetting system to create typographic quotes.

Typographic apostrophe in 8-bit encodings

Support for the typographic apostrophe ( ’ ) was introduced in several 8-bit character encodings, such as the original Apple Macintosh operating system's Mac Roman character set (in 1984), and later in the CP1252 encoding of Microsoft Windows. Both sets also used this code point for a closing single quote. There is no such character in ISO 8859-1.

The Microsoft Windows code page CP1252 (sometimes incorrectly called ANSI or ISO-Latin) contains the typographic apostrophe at 0x92. Due to "smart quotes" in Microsoft software converting the ASCII apostrophe to this value, other software makers have been effectively forced to adopt this as a de facto convention. For instance, the HTML5 standard specifies that this value is interpreted as this character from CP1252. Some earlier non-Microsoft browsers would display a '?' for this and make web pages composed with Microsoft software somewhat hard to read.

Entering apostrophes

Although ubiquitous in typeset material, the typographic apostrophe ( ’ ) is rather difficult to enter on a computer, since it does not have its own key on a standard keyboard. Outside the world of professional typesetting and graphic design, many people do not know how to enter this character and instead use the typewriter apostrophe ( ' ). The typewriter apostrophe has always been considered tolerable on Web pages because of the egalitarian nature of Web publishing, the low resolution of computer monitors in comparison to print, and legacy limitations provided by ASCII.

More recently, the standard use of the typographic apostrophe is becoming more common on the Web due to the wide adoption of the Unicode text encoding standard, higher-resolution displays, and advanced anti-aliasing of text in modern operating systems. Because typewriter apostrophes are now often automatically converted to typographic apostrophes by word processing and desktop publishing software, the typographic apostrophe does often appear in documents produced by non-professionals, albeit sometimes incorrectly—see the section "Smart Quotes" below.

How to enter typographic apostrophes on a computer (US keyboard layout)

Unicode	(Decimal)	macOS	Windows-1252 Alt code	Linux/X	HTML entity
U+2019	8217	⌥ Option+⇧ Shift+]	Alt+0146 on number pad	AltGr+⇧ Shift+N or Compose'> or Ctrl+⇧ Shift+U2019↵ Enter	’

XML (and hence XHTML) defines an ' character entity reference for the ASCII typewriter apostrophe. ' is officially supported in HTML since HTML 5. It is not defined in HTML 4 despite all the other predefined character entities from XML being defined. If it cannot be entered literally in HTML, a numeric character reference could be used instead, such as ' or '.

In the HTML entity ’ the rsquo is short for 'right single quotation mark'.

Smart quotes

To make typographic apostrophes easier to enter, word processing and publishing software often convert typewriter apostrophes to typographic apostrophes during text entry (at the same time converting opening and closing single and double quotes to their standard left-handed or right-handed forms). A similar facility may be offered on web servers after submitting text in a form field, e.g. on weblogs or free encyclopedias. This is known as the smart quotes feature; apostrophes and quotation marks that are not automatically altered by computer programs are known as dumb quotes.

Such conversion is not always correct. Smart quotes features often incorrectly convert a leading apostrophe to an opening quotation mark (e.g., in abbreviations of years: ‘29 rather than the correct ’29 for the years 1929 or 2029 (depending on context); or ‘twas instead of ’twas as the archaic abbreviation of it was). Smart quote features also often fail to recognise situations when a prime rather than an apostrophe is needed; for example, incorrectly rendering the latitude 49° 53′ 08″ as 49° 53’ 08”.

In Microsoft Word it is possible to turn smart quotes off (in some versions, by navigating through Tools, AutoCorrect, AutoFormat as you type, and then unchecking the appropriate option). Alternatively, typing Control-Z (for Undo) immediately after entering the apostrophe will convert it back to a typewriter apostrophe. In Microsoft Word for Windows, holding down the Control key while typing two apostrophes will produce a single typographic apostrophe.

Programming

Some programming languages, like Pascal, use the ASCII apostrophe to delimit string literals. In many languages, including JavaScript, ECMAScript, and Python, either the apostrophe or the double quote may be used, allowing string literals to contain the other character (but not to contain both without using an escape character), e.g. foo='He said "Bar!"';. Strings delimited with apostrophes are often called single quoted. Some languages, such as Perl, PHP, and many shell languages, treat single quoted strings as "raw" strings, while double quoted strings have expressions (such as "$variable") replaced with their values when interpreted.

The C programming language (and many derived languages like C++, Java, C#, and Scala) uses apostrophes to delimit a character literal. In these languages a character is a different object than a one-letter string.

In C++, since C++14, apostrophes can be included as optional digit separators in numeric literals.

In Visual Basic (and earlier Microsoft BASIC dialects such as QuickBASIC) an apostrophe is used to denote the start of a comment.

In the Lisp family of programming languages, an apostrophe is shorthand for the quote operator.

In Rust, in addition to being used to delimit a character literal, an apostrophe can start an explicit lifetime.

See also

• Apologetic apostrophe – use of apostrophe in Modern Scots orthography, marking the absence of a consonant in a Standard English cognatePages displaying wikidata descriptions as a fallback
• Caron ("Hacek")
• Contraction (grammar)
• Genitive case
• Modifier letter double apostrophe
• Possessive case

Notes and references

Bibliography

• Truss, Lynne (2003). Eats, Shoots & Leaves: The Zero Tolerance Approach to Punctuation. London: Profile Books. ISBN 1861976127.