noun, often capitalized, often attributive
\ ˈem How to pronounce m (audio) \
plural m's or ms\ ˈemz How to pronounce ms (audio) \

Definition of m

 (Entry 1 of 4)

1a : the 13th letter of the English alphabet
b : a graphic representation of this letter
c : a speech counterpart of orthographic m
2 : one thousand — see Table of Numbers
3 : a graphic device for reproducing the letter m
4 : one designated m especially as the 13th in order or class
5 : something shaped like the letter M


abbreviation (1)

Definition of m (Entry 2 of 4)

1 male
2 manual
3 married
4 martyr
5 masculine
6 mass
7 measure
8 meridian
9 [ Latin meridies ] noon
10 meter
11 middle
12 mile
13 [ Latin mille ] thousand
14 milli-
15 minute
16 molal; molality
17 mole
18 month
19 moon
20 morning
21 muscle


abbreviation (2)

Definition of M (Entry 3 of 4)

1 Mach
2 magnitude
3 March
4 May
5 medium
6 mega-
7 million
8 molar; molarity
9 monsieur


abbreviation (3)

Definition of m- (Entry 4 of 4)


Examples of m in a Sentence


a word that starts with an m a word that starts with m

First Known Use of m


before the 12th century, in the meaning defined at sense 1a

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Dictionary Entries near m







M'Clure Strait

Statistics for m

Look-up Popularity

Time Traveler for m

The first known use of m was before the 12th century

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English Language Learners Definition of m

: the 13th letter of the English alphabet
: the Roman numeral that means 1,000


noun, often capitalized
\ ˈem How to pronounce m (audio) \
plural m's or ms\ ˈemz \

Kids Definition of m

1 : the 13th letter of the English alphabet
2 : 1000 in Roman numerals

Kids Definition of m.

1 male
2 meter
3 mile

Medical Definition of m

 (Entry 1 of 4)

1 Mach
2 male
3 married
4 masculine
5 mass
6 meter
7 [ Latin mille ] thousand
8 million
9 minim
10 minute
11 molal
12 molality
13 molar
14 molarity
15 mole
16 mucoid
17 muscle

Medical Definition of m- (Entry 2 of 4)



\ ˈem How to pronounce M (audio) \
plural M's or Ms

Medical Definition of M (Entry 3 of 4)

: an antigen of human blood that shares a common genetic locus with the N antigen

Medical Definition of M (Entry 4 of 4)

1 [ Latin misce ] mix used in writing prescriptions
2 mitosis — see m phase

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More from Merriam-Webster on m

Rhyming Dictionary: Words that rhyme with m

Spanish Central: Translation of m

Nglish: Translation of m for Spanish Speakers

Britannica.com: Encyclopedia article about m

Comments on m

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