[ S or U ] abbreviation for medium: used to refer to someone or something, usually an item of clothing, that is of medium or average size: I like the sweater but I can't find an M. in M The shirts come in S, M, and L. Learn how to pronounce and use the letter "m" in English words and expressions. Find out the sound, multigraphs, and uses of "m" in the alphabet, numbers, and abbreviations. Learn the letter M. This Alphabet song in our Let’s Learn About the Alphabet Series is all about the consonant m Your children will be engaged in singing, li... M definition: the thirteenth letter of the English alphabet, a consonant.. See examples of M used in a sentence.
