Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “M”

See all translations

M

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

M

number ( also m)  /em/ us  

M number (NUMBER)

the Roman numeral for the number 1000

M

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)
What is the pronunciation of M?
Add Cambridge dictionaries to your browser to your website

More American English definitions for “M”

Definitions of “M” in other dictionaries

Word of the Day

be as cold as ice

to be extremely cold

Word of the Day

Cleavage proves divisive in Cambridge’s words of 2014

by Alastair Horne,
December 19, 2014
​​​​ Other dictionaries may choose faddish novelties as their words of the year, but here at Cambridge, we like to do something different. We look for the words that have seen sudden surges in searches over the course of the year – words that have been baffling users of English and driven them

Read More 

cinderella surgery noun

December 15, 2014
cosmetic surgery to the feet We have all heard of people having nose jobs, boob jobs and liposuction – but now a new trend growing in popularity in America: Cinderella surgery.

Read More