Usually means: Letter, fifteenth in English alphabet.
Definitions Related words Phrases Mentions Lyrics History
We found 26 dictionaries that define the word O:

General (16 matching dictionaries)
  1. o: Longman Dictionary of Contemporary English
  2. -o, -o-, o-: Merriam-Webster
  3. -o, -o-, o-: Oxford Learner's Dictionaries
  4. O'-, -o, -o-, o-: Collins English Dictionary
  5. O', -o, -o-, o', o-: Wiktionary
  6. -o, o-: Webster's New World College Dictionary, 4th Ed.
  7. o-: The Wordsmyth English Dictionary-Thesaurus
  8. O(M&T), -o, -o-, o-: Dictionary.com
  9. O(1), O(2), O(n), O-, O (Cirque du Soleil), O (Coldplay song), O (Cyrillic), O (Damien Rice album), O (Disambiguation), O (Eiko Shimamiya album), O (Flowers of Hell album), O (Maki Ohguro album), O (Oh!), O (Omarion album), O (Omarion song), O (Tilly and the Wall album), O (disambiguation), O (film), O (gesture), O (kana), O (letter), O (surname), The O (political group), The O, -o: Wikipedia, the Free Encyclopedia
  10. O': Online Plain Text English Dictionary
  11. O': AllWords.com Multi-Lingual Dictionary
  12. -o: MyWord.info
  13. -o: Stammtisch Beau Fleuve Acronyms
  14. O'-, o-: TheFreeDictionary.com
  15. O: Dictionary of Phrase and Fable (1898)
  16. o: AllWords.com Multi-Lingual Dictionary

Business (1 matching dictionary)
  1. o-: Financial dictionary

Computing (1 matching dictionary)
  1. O(1,3), O(2), O(3), O(3,1), O (element), o-: Encyclopedia

Medicine (2 matching dictionaries)
  1. O: Merriam-Webster Medical Dictionary
  2. O (element), -o-, o-: Medical dictionary

Miscellaneous (2 matching dictionaries)
  1. O(M&T): Acronym Finder
  2. AbbreviationZ (No longer online)

Science (2 matching dictionaries)
  1. O(2): PlanetMath Encyclopedia
  2. O( ), O( ), o( ), o( ): Prime

Slang (2 matching dictionaries)
  1. O: Green’s Dictionary of Slang
  2. O'----, O-, o-, o.-, the o: Urban Dictionary

(Note: See o's as well.)

Google, News, Images, Wikipedia, Reddit, BlueSky
Definitions from Wiktionary (O)

▸ noun:  The name of the Latin-script letter O/o.
▸ noun:  A zero (used in reading out numbers).
▸ noun:  (IRC, acronym of) Operator
▸ noun:  (acronym of) Object, see SVO
▸ noun:  Something shaped like the letter O.
▸ noun:  (uncountable) 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.
▸ noun:  An utterance of the vocative O.
▸ noun:  (printing) American Library Association abbreviation of octavo, a book size (20-25 cm).
▸ noun:  (soccer) Someone associated with Leyton Orient Football Club, as a player, coach, supporter etc.
▸ noun:  (cricket) The number of overs bowled.
▸ noun:  (slang) Orgasm.
▸ noun:  (slang, uncountable) Opium.
▸ noun:  A surname from Korean.
▸ noun:  A surname from Mandarin Chinese.
▸ adjective:  (Singapore, colloquial, used as a modifier after kopi (“coffee”) or teh (“tea”)) With sugar and no condensed milk added.
▸ adjective:  Clipping of over. [Finished; ended; concluded.]
▸ adjective:  (historical) Abbreviation of morally offensive. (film classification of the National Legion of Decency)
▸ adjective:  (Judaism) Abbreviation of Orthodox. [(Christianity) Of or pertaining to the Orthodox Churches collectively.]
▸ noun:  Alternative form of E (Ancient Chinese Kingdom) [(slang) The drug ecstasy (MDMA), particularly in pill form.]

Similar:
bone, osmium, operating system, atomic number 76, bf, hea, pos, tr, sop, Af, more...

Opposite:
inside, internal, interior, inward, central

Types:
zero, oh, letter o, numeral o, circle o, big o, small o, more...

Phrases:
o f, h o, t o, o n, I o, more...



▸ Words similar to O

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▸ Popular adjectives describing O

▸ Popular nouns described by O

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▸ Rhymes of O

▸ Invented words related to O

Similar:
bone, osmium, operating system, atomic number 76, bf, hea, pos, tr, sop, Af, more...

Opposite:
inside, internal, interior, inward, central

Types:
zero, oh, letter o, numeral o, circle o, big o, small o, more...

Phrases:
o f, h o, t o, o n, I o, jell o, o ring, will o the wisp, c o, jack o lantern, cat o nine tails, O level, o r, tam o shanter, w o, d o, o henry, light o love, o t, o c, more...



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