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o

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onoun
orO/ˈoʊ/
pluralo'sorosorO'sorOs/ˈoʊz/
o
noun
or O /ˈoʊ/
pluralo'sorosorO'sorOs/ˈoʊz/
Learner's definition of O  
: the 15th letter of the English alphabet
[count]
[noncount]
[count]  : the number zero — used in speech when referring to numbers
[count]  — used as a mark at the end of a letter, an e-mail, etc., to represent a hug
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