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English definition of “O, o”

O, o

noun [C or U] uk   /əʊ/ us    // (plural Os, O's or o's)

O, o noun [C or U] (LETTER)

the 15th letter of the English alphabetLetters of alphabetsLettering and alphabets

O, o noun [C or U] (ZERO)

(also o, also oh) used in speech to mean zero: My phone number is three, one, o, five, one, double o (= 3105100). The year 1705 is usually pronounced seventeen o five.Cardinal numbers, including nought and zero

O, o

exclamation uk   /əʊ/ us    // old use or literary
used when talking to someone or something, or expressing something in an emotional or formal way: O Zeus! Hear my prayer. InterjectionsSounds used as interjections
(Definition of O, o from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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