o

O1
UK/əʊ/US/oʊ//ʌ/Singapore[ˈoː˦]

character

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

“The system's Bayer designation is o Persei.”

Similar
big Ooxygenatomic number 8type Ogroup O
Very commonScrabble 1

Meanings

o1

character

uppercase O · plural os · plural o's

  1. letterlowercaseThe fifteenth letter of the English alphabet, called o and written in the Latin script.
  2. alternativeletterlowercaseAlternative form of ο, the fifteenth letter of the Classical and Modern Greek alphabets, called omicron and (astronomy) used as an abbreviation of omicron in star names.

    The system's Bayer designation is o Persei.

numeral

uppercase O · plural os · plural o's

  1. lowercaseThe fifteenth numeral symbol of the English alphabet, called o and written in the Latin script.
nouno (plural oes)

plural oes · alternative oh

  1. The name of the Latin script letter O/o.
  2. A zero (used in reading out numbers).

    It is currently two-o-five in the afternoon (2:05 PM).

    1 more example

    The first permanent English settlement in America was in Jamestown in sixteen-o-seven (1607).

o2

particle
  1. alternativenonstandardalternative form of O (vocative particle)

    I lift my soule to thee o Lord mee, o Iehovah, heare In thee, o Lord, I put my trust

    2007, The Bay Psalm Book, Cosimo Classics, published 1640, p.37, 41 & 46
interjection
  1. alternativeAlternative form of oh.
noun
  1. InternetabbreviationacronymIRCOperator
  2. abbreviationacronymObject, see SVO
adjective
  1. abbreviationclippingClipping of over.

o3

preposition
  1. alternativeAlternative form of of.

O4

character

lowercase o · plural Os · plural O's

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

    "Supposing somebody sees you, with all those flowers too? Supposing somebody writes him a letter? Ooooh!" (a pure round open Tamil O.)

    1959, Anthony Burgess, Beds in the East (The Malayan Trilogy), published 1972, page 421
nounO (plural Os or O's)

plural Os · plural O's

  1. Something shaped like the letter O.
    1 more example

    She was lying in the lee of a fowlhouse in a crumpled posture, as if cohesion had been detached from her joints, which lobbed her in an untidy heap, like a lot of old bones, tied together with string. Her skull was hitched under her humped shoulders and her fallen jaw made a lipless O of her mouth, giving it an expression of imbecile astonishment.

    1938, Norman Lindsay, chapter XX, in Age of Consent, London: T[homas] Werner Laurie […], →OCLC, page 213
  2. uncountableA 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.
numeral

lowercase o · plural Os · plural O's

  1. uppercaseThe fifteenth numeral symbol of the English alphabet, called o and written in the Latin script.

O5

particle

alternative o · alternative obsolete ô

  1. The vocative particle, used for direct address.

    O Death! O Death! Won't you spare me over till another year? - part of the refrain from the American folk song "A Conversation with Death".

    3 more examples

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

    1526, [William Tyndale, transl.], The Newe Testamẽt […] (Tyndale Bible), [Worms, Germany: Peter Schöffer], →OCLC, Romans ij:[1, 3], folio cc, verso

    c. 1810-1820?, Samuel Taylor Coleridge, Notes on Macbeth O! the affecting beauty of the death of Cawdor, and the presentimental speech of the king: […]

    “Lift up your head and your heart, O King. We must follow after this dreadnought, hard on her tracks.”

    1961, Norma Lorre Goodrich, “Beowulf”, in The Medieval Myths, New York: The New American Library, page 35
nounO (plural Oes)

plural Oes · alternative o · alternative obsolete ô

  1. An utterance of the vocative O.

O6

nounO (countable and uncountable, plural Os)

plural Os

  1. countableuncountablemediaAmerican Library Association abbreviation of octavo, a book size (20-25 cm).
  2. countableuncountableball gamesSomeone associated with Leyton Orient Football Club, as a player, coach, supporter etc.
  3. countableuncountableball gamesThe number of overs bowled.
  4. countableslanguncountableOrgasm.

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

    1999 March 31, JT aka GF, “Re: mary p., hex and going "downtown"”, in alt.psst.hoy (Usenet), retrieved 22 Nov 2014
    3 more examples

    Sunny felt some cold and wet press against her pussy, it startled her, then it's^([sic]) 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.

    1998 October 17, M6968, “STORY: The Violation of Sunny a wrestling story, by Wonder Mike”, in alt.sex.stories (Usenet), retrieved 22 Nov 2014

    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.

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

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

    2011 June 14, wtw, “{wtw} - "4someWithFriends" (1/1)”, in alt.sex.stories (Usenet), retrieved 22 Nov 2014

    Synonyms: big O

  5. slanguncountableOpium.

    We lay on our stomachs on the living-room floor in a circle around our host, a skinny little man who said he'd been smoking O for 20 years.

    1952, Collier's: Incorporating Features of the American Magazine, page 22
adjectiveO (not comparable)
  1. abbreviationhistoricalnot comparableAbbreviation of morally offensive, film classification of the National Legion of Decency.
  2. Judaismabbreviationnot comparableAbbreviation of Orthodox.

O7

proper noun

alternative Oh · alternative Oe · alternative Au

  1. A surname from Korean.

O8

proper noun

alternative E

  1. alternativeAlternative form of E (Ancient Chinese Kingdom)

    In ancient times Wuchang was the capital city of the Kingdom of O. In Manchu times it was the residence of the Viceroy of the two provinces of Hupeh and Hunan. Since then its fortunes have changed with changing politics.

    1944, Harold Burgoyne Rattenbury, China, My China, →OCLC, page 51
    3 more examples

    ACCORDING to various inscriptions about this famous temple we are told that it was erected to the memory of Ya Fei, "An Unswerving Guardian to the Heir-Apparent," of the Sung dynasty; "A Loyal-to-the-end Minister," who came from the ancient state of O-Kuo, the present Wu Ch'ang-fu of Hupei; and that it was erected by the Emperor Hsiao Tsung as an atonement for the weakness and follies of his father, Kao Tsung, toward a faithful servant of the empire who came to his untimely death through the diabolical schemes of men in high estate. Moreover, that after his death and burial, when the empire came to appreciate his great services to the people, the posthumous title of " Prince of O-Kuo" was bestowed upon his sacred memory.

    [1906, Frederick D. Cloud, Hangchow, the "City of Heaven", Shanghai: Presbyterian Mission Press, →OCLC, →OL, page 53

    ⁶There are actually several geographical identifications proposed for the State of O: Wu-ch'ang in Hupei, Huai-ch'ing in Honan, and Fu-fang, Shensi (in the south-east thereof). As two inscriptions connected with the State of O refer to invasions....

    1976, Noel Barnard, The Proceedings of a Symposium on Scientific Methods of Research in the Study of Ancient Chinese Bronzes and Southeast Asian Metal and Other Archaeological Artifacts, October 6-10, 1975, National Gallery of Victoria, Melbourne, →ISBN, →OCLC, →OL, page 107

    […]Yang-yüeh 楊粵,⁴⁰ reaching as far as O 鄂.⁴¹[…]He then enthroned his elder son K'ang 康⁴³ as King of Kou Tan 句亶,⁴⁴ his middle song Hung 紅 as King of O 鄂,⁴⁵ and his younger son Chih-tz'u 執疵 as King of Yüeh-chang 越章.⁴⁶

    2006, Ch'ien Ssu-ma, edited by William H. Nienhauser, Jr., The Grand Scribe's Records,, volume V.1, →ISBN, →OCLC, →OL, page 385

O9

adjectiveO (not comparable)
  1. Singaporecolloquialnot comparableWith sugar and no condensed milk added.

    Better try their kopi-o tarik. Our version nowadays taste like cough medicine. LOL!

    2003, Ixus, soc.culture.singapore (Usenet)

Synonyms & antonyms

nounOrgasm.

Similar

More synonyms by meaning

nouna nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust

Similar
oxygenatomic number 8

nounthe blood group whose red cells carry neither the A nor B antigens

Similar
type Ogroup O

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

O · particle, noun

  1. Latinō
  2. Old Frenchoh
  3. Middle Englisho
  4. EnglishO

From Middle English O, o, from Old English o, from Latin o and Ancient Greek ὦ (ô, interjection). Featured prominently in William Tyndale's 1525 translation of the New Testament.

Full word history & related roots →

O · noun, adjective

Abbreviation.

Full word history & related roots →

O · proper noun

Korean 오(伍) (O) or 오(吳) (O). Doublet of Wu.

Full word history & related roots →

O · proper noun

  1. Mandarin鄂
  2. EnglishO

From Mandarin 鄂 (È) Wade–Giles romanization: O⁴.

Full word history & related roots →

O · adjective

  1. Teochew烏 /乌“black”
  2. Hokkien烏 /乌“black”
  3. EnglishO

From Hokkien 烏 /乌 (o͘, “black”) or Teochew 烏 /乌 (ou¹, “black”).

Full word history & related roots →

Translations

Ancient Greek ὦ
  • ὦ (ô)a vocative particle
Arabic أُوه, أُوه
  • أُوه (ʔūh)name of the letter O, o
  • أُوه (ʔoh)name of the letter O, o
  • يَا (yā)a vocative particle
  • أَيُّهَا (ʔayyuhā)a vocative particle
  • أَيَّتُهَا (ʔayyatuhā)a vocative particle
  • يا (yā)a vocative particle
Bengali ও
  • ও (ō)name of the letter O, o
Bulgarian о
  • о (o)name of the letter O, o
Catalan o, oh
  • oname of the letter O, o
  • oha vocative particle
  • oa vocative particle
Chinese Mandarin 噢, 喔
  • 噢 (ō)a vocative particle
  • 喔 (ō)a vocative particle
  • 啊 (ā)a vocative particle
  • 噫 (yì)a vocative particle
Esperanto o, ho
  • oname of the letter O, o
  • hoa vocative particle
Finnish oo, oi
  • ooname of the letter O, o
  • oia vocative particle
French o, ô
  • oname of the letter O, o
  • ôa vocative particle
German o
  • oa vocative particle
Greek όου
  • όου (óou)name of the letter O, o
Hawaiian ʻō
  • ʻōname of the letter O, o
Hebrew הו
  • הו (ho)a vocative particle
Hindi ओ, हे
  • ओ (o)name of the letter O, o
  • हे (he)a vocative particle
Irish ó, onn
  • óname of the letter O, o
  • onnname of the letter O, o
  • aa vocative particle
Italian o, oh
  • oa vocative particle
  • oha vocative particle
Japanese オウ, よ
  • オウ (ō)name of the letter O, o
  • よ (yo)a vocative particle
  • ああ (ā)a vocative particle
Korean 오, 여
  • 오 (o)name of the letter O, o
  • 여 (yeo)a vocative particle
  • 시여 (siyeo)a vocative particle
  • 아 (a)a vocative particle
Latin ō, o
  • ōname of the letter O, o
  • oa vocative particle
Malay o, wahai
  • oname of the letter O, o
  • wahaia vocative particle
Persian ای, الا
  • ای (ey)a vocative particle
  • الا (alâ)a vocative particle
Polish o
  • oa vocative particle
Portuguese ó, ô
  • óname of the letter O, o
  • ôname of the letter O, o
  • óa vocative particle
Russian о́у, о
  • о́у (óu)name of the letter O, o
  • о (o)name of the letter O, o
  • о (o)a vocative particle
Scottish Gaelic a
  • aa vocative particle
Spanish o, oh
  • oname of the letter O, o
  • oha vocative particle
  • oya vocative particle
Swedish o
  • oa vocative particle
Tagalog oh
  • oha vocative particle
Thai โอ
  • โอ (oo)name of the letter O, o
Turkish o, ey
  • oname of the letter O, o
  • eya vocative particle
  • yaa vocative particle
Ukrainian о
  • о (o)a vocative particle
Urdu اَے
  • اَے (ai)a vocative particle
Vietnamese o, hỡi
  • oname of the letter O, o
  • hỡia vocative particle
  • lạya vocative particle
  • ôia vocative particle

Rhymes & wordplay

Rhymes with o

All rhymes →

Sounds the same

Ooeohowe (toe–tow merger)Ooeohowe (toe–tow merger)Ooeohowe (toe–tow merger)
Cite this entry
APA

o. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/o

MLA

“o.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/o. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “o,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/o.

Source: o on Wiktionary, CC BY-SA 4.0.