O

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O is the fifteenth (number 15) letter in the English alphabet and it has a shape of a circle.

It appears after “N” and before “P”.

 Meanings for Letter O 
 On calendars, O sometimes means the month October.
 In chemistry, O represents the symbol "oxygen".
 In medicine, O is one of the human blood types.
 Sometimes when saying decimals, O is another word for 0.

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Category:Vowel letters