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English definition of “M”

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noun [C] ( plural M’s, Ms, m’s or ms) ( also m)  /em/ us  

M noun [C] (LETTER)

the 13th letter of the English alphabet


number ( also m)  /em/ us  

M number (NUMBER)

the Roman numeral for the number 1000


adjective [not gradable]  /em/ us  

M adjective [not gradable] (SIZE)

abbreviation for medium Note: Used esp. on clothing to show its size.
(Definition of M noun, number, adjective from the Cambridge Academic Content Dictionary © Cambridge University Press)
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