O

O U+004F, O LATIN CAPITAL LETTER O ← N [U+004E] Basic Latin P → [U+0050]

Ｏ U+FF2F, Ｏ FULLWIDTH LATIN CAPITAL LETTER O ← Ｎ [U+FF2E] Halfwidth and Fullwidth Forms Ｐ → [U+FF30]

See also: o, ö, ő, and Appendix:Variations of "o"

Translingual

Letter

O (lower case o)

1. The fifteenth letter of the basic modern Latin alphabet.

See also

• (Latin script):  Aa  Bb  Cc  Dd  Ee  Ff  Gg  Hh  Ii  Jj  Kk  Ll  Mm  Nn  Oo  Pp  Qq  Rr  Sſs  Tt  Uu  Vv  Ww  Xx  Yy  Zz
• (Variations of letter O):  Óó  Òò  Ŏŏ  Ôô  Ốố  Ồồ  Ỗỗ  Ổổ  Ǒǒ  Öö  Ȫȫ  Őő  Õõ  Ṍṍ  Ṏṏ  Ȭȭ  Ȯȯ  Ȱȱ  Øø  Ǿǿ  Ǫǫ  Ǭǭ  Ōō  Ṓṓ  Ō̂ō̂  Ṑṑ  Ỏỏ  Ȍȍ  Ȏȏ  Ơơ  Ớớ  Ờờ  Ỡỡ  Ởở  Ợợ  Ọọ  Ộộ  Ɵɵ  ⱺ  ᴏ  Ｏｏ  Ꜵꜵ  Œœ  Ꝏꝏ  Ꝍꝍ  Ȣȣ

Symbol

O

1. (chemistry) Symbol for oxygen.
2. (mathematics) big O: a class of functions asymptotically bounded from above by a specific function, up to a constant factor
3. (linear algebra, group theory) orthogonal group

Gallery

• Letter styles
• 

  Normal and italic O

• 

  Uppercase and lowercase O in Fraktur

See also

Other representations of O:

NATO phonetic: Oscar Morse code: ––– Braille: ⠕ ASL Manual: O

Signal flag:

Semaphore:

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English

Alternative forms

• o (for the vocative particle)

Etymology 1

Pronunciation

• (UK) IPA^(key): /əʊ/

  Audio (UK)

  (file)

• (US) IPA^(key): /oʊ/

  Audio (US)

  (file)

Letter

O (upper case, lower case o, plural Os or O's)

1. The fifteenth letter of the English alphabet, called o and written in the Latin script.

Noun

O (uncountable)

1. A blood type that lacks A or B antigens and may only receive transfusions of similar type O blood, but may donate to all (neglecting Rh factor). Synonym: universal donor.

See also

• (Latin-script letters) letter; A a, B b, C c, D d, E e, F f, G g, H h, I i, J j, K k, L l, M m, N n, O o, P p, Q q, R r, S s, T t, U u, V v, W w, X x, Y y, Z z

Number

O (upper case, lower case o)

1. The ordinal number fifteenth, derived from this letter of the English alphabet, called o and written in the Latin script.

Etymology 2

English O, o is attested in William Tyndale's 1525 New Testament Translation, as a translation of Ancient Greek ὦ (ô, interjection), Latin o. (Compare the Old English particles ēalā, ǣlā, hēlā.) In Middle English, O is found in Acts 13:10, Romans 9:20 and Galatians 3:1, and ò is found in Romans 2:1,3, of John Wycliff's Newe Testament (1382). Compare la (a particle for introducing a statement or expressing surprise), from Old English; compare also English lo, oh.

Compare the Old Saxon gloss o (950s) of the Lambeth MS (957) of the Gallican Psalter and the ó, o (post-1000) of the Durham Hymns, regularly seen in the redundant forms "o eala þu" and "ó eala þu" by proper names.

Compare also the Anglo-Norman O (about 1200) of the manuscripts of Saints Juliana and Katherine, and other religious writs.

Particle

O

1. The English vocative particle, used for direct address.
   • 1525, Tyndale's translation of Romans 2.1,3:

     Therefore arte thou inexcusable o man whosoever thou be that iudgest. For in that same where in thou iudgest another, thou cõdemnest thysilfe. For thou that iudgest doest evẽ the same silfe thynges. […] Thynkest thou O man that iudgest them which do soche thyngs and yet dost evẽ the very same, that thou shalt escape the iudgemẽt of God?

   • Samuel Taylor Coleridge

     O! the affecting beauty of the death of Cawdor, and the presentimental speech of the king: […]

   • For more examples of usage of this term, see Citations:O.

Usage notes

• The word O is always written in upper case in modern usage.
• O is often used in translations from languages which have the vocative case.
• Although it is not strictly archaic, the particle is sometimes used archaizingly. It conveys a formal or reverential tone.

Derived terms

• O Canada

Translations

a vocative particle

• Ancient Greek: ὦ (ô)
• Arabic: يَا‏‎ (ar) (yā), أَيُّهَا‏‎ m (ʾayyuhā), أَيَّتُهَا‏‎ f (ʾayyatuhā)

  Egyptian Arabic: يا‏‎ (ya)

• Catalan: oh, o (ca)
• Chinese:
• French: ô (fr)
• German: o (de)
• Irish: a (ga)

  Old Irish: a, á

• Japanese: よ (ja) (yo)
• Korean: 여 (ko) (yeo), 시여 (siyeo)
• Latin: o (la)

• Malay: wahai
• Mandarin: 噢 (zh) (ō), 喔 (zh) (ō)
• Persian: ای‏‎ (fa) (ey), الا‏‎ (fa) (alā)
• Portuguese: ó (pt)
• Russian: о (ru) (o)
• Sanskrit: हे (sa) (he)
• Spanish: oh (es), oy (es) m
• Swedish: o (sv)
• Tagalog: oh (formally)
• Turkish: ey (tr)
• Ukrainian: о (uk) (o)

Synonyms

• oh
• hey
• yo
• ah

Etymology 3

Abbreviation.

Abbreviation

O

1. (cricket) The number of overs bowled.
2. (slang) Orgasm. (Often used in the phrase the big O.)
   • 1998 October 17, M6968, “STORY: The Violation of Sunny a wrestling story, by Wonder Mike”, in alt.sex.stories, Usenet^[1], retrieved November 22, 2014:

     Sunny felt some cold and wet press against her pussy, it startled her, then it's tongue went deep inside of her, she had been eaten out before, but never this could, who ever was doing it was a real pro, and had to have the longest tongue in the world it was buried at least three inches inside of her and was taking long, hard strokes, it was trying to get even deeper, it was only seconds before she started shaking from her first O.

   • 1999 March 31, JT aka GF, “Re: mary p., hex and going "downtown"”, in alt.psst.hoy, Usenet^[2], retrieved November 22, 2014:

     Further on, when she's about to reach her first O, the taste turns from no taste to champagne-like.

   • 2010, Lonnie Hicks, Einstein, Religion, Politics and Literature, page 308:

     She thought you could get pregnant from tonguing when kissing; about her first O and how it scared her; how she looked in the mirror afterwards to see if she had changed; about how scared she was when it came time to deliver the baby.

   • 2011 June 14, wtw, “{wtw} - "4someWithFriends" (1/1)”, in alt.sex.stories, Usenet^[3], retrieved November 22, 2014:

     Now my friend was fingering my wife and licking her clit. My wife reached her first O of the night.

Noun

O (uncountable)

1. (printing) American Library Association abbreviation of octavo, a book size (20-25 cm).
2. (soccer) Someone associated with Leyton Orient Football Club, as a player, coach, supporter etc.

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Afar

Letter

1. The fifteenth letter in the Afar alphabet.

See Also

• (Latin-script letters) A a, B b, T t, S s, E e, C c, K k, X x, I i, D d, Q q, R r, F f, G g, O o, L l, M m, N n, U u, W w, H h, Y y

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American Sign Language

Letter

(transliteration needed) (Stokoe O)

1. The letter O

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Azeri

Letter

O upper case (lower case o)

1. The twenty-first letter of the Azeri alphabet, written in the Latin script.

See also

• (Latin-script letters) hərf; A a, B b, C c, Ç ç, D d, E e, Ə ə, F f, G g, Ğ ğ, H h, X x, I ı, İ i, J j, K k, Q q, L l, M m, N n, O o, Ö ö, P p, R r, S s, Ş ş, T t, U u, Ü ü, V v, Y y, Z z

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Dutch

Pronunciation

• (letter name): IPA^(key): /oː/

• Audio

  (file)

Letter

O (capital, lowercase o)

1. The fifteenth letter of the Dutch alphabet.

Abbreviation

O

1. Abbreviation of oost; east

See also

• Previous letter: N
• Next letter: P

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Esperanto

Letter

O (upper case, lower case o)

1. The nineteenth letter of the Esperanto alphabet, called o and written in the Latin script.

See also

• (Latin-script letters) litero; A a, B b, C c, Ĉ ĉ, D d, E e, F f, G g, Ĝ ĝ, H h, Ĥ ĥ, I i, J j, Ĵ ĵ, K k, L l, M m, N n, O o, P p, R r, S s, Ŝ ŝ, T t, U u, Ŭ ŭ, V v, Z z

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Finnish

Letter

O (upper case, lower case o)

1. The fifteenth letter of the Finnish alphabet, called oo and written in the Latin script.

See also

• (Latin-script letters) kirjain; A a, B b, C c, D d, E e, F f, G g, H h, I i, J j, K k, L l, M m, N n, O o, P p, Q q, R r, S s, Š š, T t, U u, V v, W w, X x, Y y, Z z, Ž ž, Å å, Ä ä, Ö ö

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French

Pronunciation

• (letter) IPA^(key): /o/

• Audio (Paris)

  (file)

Abbreviation

O

1. Abbreviation of ouest; west

Letter

O

1. The fifteenth letter of the French alphabet.

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Galician

Abbreviation

O

1. oeste, occidente (west)

Synonyms

• (west): W

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German

Pronunciation

• IPA^(key): /ʔoː/

• Audio

  (file)

Letter

O (upper case, lower case o)

1. The fifteenth letter of the German alphabet.

Abbreviation

O

1. Abbreviation of Ost; east

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Italian

Pronunciation

• (name of letter) IPA^(key): /ɔ/
• Homophone: ho
• (phoneme) IPA^(key): /o/, /ɔ/
• Homophones: o, ho

Letter

O m, f (invariable, lower case o)

1. The thirteenth letter of the Italian alphabet, called o and written in the Latin script.

See also

• (Latin-script letters) lettera; A a (À à), B b, C c, D d, E e (É é, È è), F f, G g, H h, I i (Í í, Ì ì, Πî, J j, K k), L l, M m, N n, O o (Ó ó, Ò ò), P p, Q q, R r, S s, T t, U u (Ú ú, Ù ù), V v (W w, X x, Y y), Z z
• Italian alphabet on Wikipedia.Wikipedia

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Korean

Alternative forms

• ○ (rare)

Etymology

From Japanese ○ (maru).

Symbol

O

1. true.

Antonyms

• X

Derived terms

• OX

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Latvian

Etymology

Proposed in 1908 as part of the new Latvian spelling by the scientific commission headed by K. Mīlenbahs, which was accepted and began to be taught in schools in 1909. Prior to that, Latvian had been written in German Fraktur, and sporadically in Cyrillic.

Pronunciation

• IPA^(key): [uə̯], IPA^(key): [o], IPA^(key): [oː]

Letter

O

O (upper case, lower case o)

1. The twenty-third letter of the Latvian alphabet, called o and written in the Latin script.

Usage notes

In native Latvian words (and in some older borrowings), o represents the sound of IPA [uə̯] (e.g., otrs [uə̯tɾs]). In more recent borrowings, it represents the original sound of the word, i.e. [o] or [oː] (e.g., opera [oːpeɾa]).

See also

• Letters of the Latvian alphabet:

  burti: Aa, Āā, Bb, Cc, Čč, Dd, Ee, Ēē, Ff, Gg, Ģģ, Hh, Ii, Īī, Jj, Kk, Ķķ, Ll, Ļļ, Mm, Nn, Ņņ, Oo, Pp, Rr, Ss, Šš, Tt, Uu, Ūū, Vv, Zz, Žž

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Malay

Pronunciation

• (Name of letter) IPA^(key): [o]
• (Phoneme) IPA^(key): [o], [ɔ]

Letter

O

1. The fifteenth letter of the Malay alphabet, written in the Latin script.

See also

• (Latin-script letters) A a, B b, C c, D d, E e, F f, G g, H h, I i, J j, K k, L l, M m, N n, O o, P p, Q q, R r, S s, T t, U u, V v, W w, X x, Y y, Z z

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Portuguese

Letter

O (upper case, lower case o)

1. The fifteenth letter of the Portuguese alphabet, written in the Latin script.

See also

• (Latin-script letters) letra; A a (Á á, À à,  â, àã), B b, C c (Ç ç), D d, E e (É é, Ê ê), F f, G g, H h, I i (Í í), J j, K k, L l, M m, N n, O o (Ó ó, Ô ô, Õ õ), P p, Q q, R r, S s, T t, U u (Ú ú), V v, W w, X x, Y y, Z z

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Romanian

Pronunciation

• IPA^(key): /o/

Letter

O (capital, lowercase o)

1. The eighteenth letter of the Romanian alphabet representing the phoneme /o/. Preceded by N and followed by P.

Usage notes

When followed by the letter a, a diphthong representing the phoneme /o̯a/ is formed, as in foarte /'fo̯ar.te/

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Saanich

Pronunciation

• IPA^(key): /ɑ/

Letter

O

1. The twenty-third letter of the Saanich alphabet, written in the Latin script.

See also

• (Latin-script letters) A, Á, Ⱥ, B, C, Ć, Ȼ, D, E, H, I, Í, J, K, Ꝁ, Ꝃ, ₭, Ḵ, Ḱ, L, Ƚ, M, N, Ṉ, O, P, Q, S, Ś, T, Ⱦ, Ṯ, Ŧ, U, W, W̲, X, X̲, Y, Z, s, ,

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Skolt Sami

Pronunciation

• (phoneme) IPA^(key): /o/

Letter

O (lower case o)

1. The twenty-fourth letter of the Skolt Sami alphabet, written in the Latin script.

See also

• (Latin-script letters) bukva; A a,  â, B b, C c, Č č, Ʒ ʒ, Ǯ ǯ, D d, Đ đ, E e, F f, G g, Ǧ ǧ, Ǥ ǥ, H h, I i, J j, K k, Ǩ ǩ, L l, M m, N n, Ŋ ŋ, O o, Õ õ, P p, R r, S s, Š š, T t, U u, V v, Z z, Ž ž, Å å, Ä ä, ʹ

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Slovene

Letter

O (capital, lowercase o)

1. The 16th letter of the Slovene alphabet. Preceded by N and followed by P.

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Somali

Pronunciation

• (phoneme): IPA^(key): /ɔ/, /ɞ/
• (letter name): IPA^(key): /ʔɔ/

Letter

O upper case (lower case o)

1. The twenty-sixth letter of the Somali alphabet, called o and written in the Latin script.

Usage notes

• The twenty-sixth letter of the Somali alphabet, which follows Arabic abjad order. It is preceded by I and followed by U.

See also

• (Latin-script letters) ', B b, T t, J j, X x, Kh kh, D d, R r, S s, Sh sh, Dh dh, C c, G g, F f, Q q, K k, L l, M m, N n, W w, H h, Y y, A a, E e, I i, O o, U u

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Spanish

Letter

O (upper case, lower case o)

1. The 16th letter of the Spanish alphabet.

Abbreviation

O

1. Abbreviation of oeste; west

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Turkish

Letter

O (upper case, lower case o)

1. The eighteenth letter of the Turkish alphabet, called o and written in the Latin script.

See also

• (Latin-script letters) harf; A a, B b, C c, Ç ç, D d, E e, F f, G g, Ğ ğ, H h, I ı, İ i, J j, K k, L l, M m, N n, O o, Ö ö, P p, R r, S s, Ş ş, T t, U u, Ü ü, V v, Y y, Z z

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Vietnamese

Pronunciation

• (Hà Nội) IPA^(key): [ʔɔ˧˧], [ʔo˧˧]
• (Huế) IPA^(key): [ʔɔ˧˧], [ʔow˧˧]
• (Hồ Chí Minh City) IPA^(key): [ʔɔ˧˥], [ʔow˧˥]
• Phonetic: o, ô

Letter

O (upper case, lower case o)

1. The seventeenth letter of the Vietnamese alphabet, called o or ô and written in the Latin script.

See also

• (Quốc ngữ letters) chữ; A a (À à, Ả ả, àã, Á á, Ạ ạ), Ă ă (Ằ ằ, Ẳ ẳ, Ẵ ẵ, Ắ ắ, Ặ ặ),  â (Ầ ầ, Ẩ ẩ, Ẫ ẫ, Ấ ấ, Ậ ậ), B b, C c (Ch ch), D d, Đ đ, E e (È è, Ẻ ẻ, Ẽ ẽ, É é, Ẹ ẹ), Ê ê (Ề ề, Ể ể, Ễ ễ, Ế ế, Ệ ệ), G g (Gh gh, Gi gi), H h, I i (Ì ì, Ỉ ỉ, Ĩ ĩ, Í í, Ị ị), K k (Kh kh), L l, M m, N n (Ng ng, Ngh ngh, Nh nh), O o (Ò ò, Ỏ ỏ, Õ õ, Ó ó, Ọ ọ), Ô ô (Ồ ồ, Ổ ổ, Ỗ ỗ, Ố ố, Ộ ộ), Ơ ơ (Ờ ờ, Ở ở, Ỡ ỡ, Ớ ớ, Ợ ợ), P p (Ph ph), Q q (Qu qu), R r, S s, T t (Th th, Tr tr), U u (Ù ù, Ủ ủ, Ũ ũ, Ú ú, Ụ ụ), Ư ư (Ừ ừ, Ử ử, Ữ ữ, Ứ ứ, Ự ự), V v, X x, Y y (Ỳ ỳ, Ỷ ỷ, Ỹ ỹ, Ý ý, Ỵ ỵ)

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Zulu

Letter

O (upper case, lower case o)

1. The fifteenth letter of the Zulu alphabet, written in the Latin script.

See also

• (Latin-script letters) A a, B b, C c, D d, E e, F f, G g, H h, I i, J j, K k, L l, M m, N n, O o, P p, Q q, R r, S s, T t, U u, V v, W w, X x, Y y, Z z