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definitions

M, m

[em]
|

noun, plural M's or Ms, m's or ms.

the thirteenth letter of the English alphabet, a consonant.
any spoken sound represented by the letter M or m, as in my, summer, or him.
something having the shape of an M.
a written or printed representation of the letter M or m.
a device, as a printer's type, for reproducing the letter M or m.
Printing. em.

m

Physics. mass.
Finance. (of bonds) matured.
medieval.
medium.
meter; meters.
middle.
Music. minor.

m

Symbol, Electricity. magnetic pole strength.

M

mach.
Music. major.
male.
married.
Medieval.
medium.
mega-.
Middle.
modal auxiliary.
modifier.
Economics. monetary aggregate: issued periodically by the Federal Reserve Board as various measures of money supply (M-1, M-1A, M-2, etc.).Compare L
British. motorway (used with a road number to designate a major highway): the M1.

M

Symbol.

the thirteenth in order or in a series, or, when I is omitted, the twelfth.
(sometimes lowercase) the Roman numeral for 1000.Compare Roman numerals.
Electricity. magnetization.
Biochemistry. methionine.

Mac-

a prefix found in many family names of Irish or Scottish Gaelic origin, as MacBride and Macdonald.
Also Mc- Mc-, M'-.

Origin of Mac-

< Irish, Scots Gaelic mac son, Old Irish macc; akin to Welsh, Cornish mab

'm

[m]

contraction of am: I'm not thirsty.

m-

meta-.
(referring especially to the use of wireless electronic devices) mobile: m-commerce; m-business.

M-

U.S. Military. (used to designate the production model of military equipment, as the M-1 rifle.)

M'-

variant of Mac-.

m.

1

noon.

Origin of m.

1
From the Latin word merīdiēs

m.

2

(in prescriptions) mix.

Origin of m.

2
From the Latin word misce

m.

3

male.
(in Germany) mark; marks.
married.
masculine.
Physics. mass.
medium.
meter.
middle.
mile.
minute.
modification of.
modulus.
molar.
month.
moon.
morning.
mouth.

M.

1

or m.

noon.

Origin of M.

1
From the Latin word merīdiēs

M.

2

Majesty.
Manitoba.
markka; markkaa.
Marquis.
Music. measure.
medicine.
medium.
meridian.
Monday.
plural MM. Monsieur.
mountain.

Mc-

2

variant of Mac-.
Also Mc-.

mu

[myoo, moo]

noun

the 12th letter of the Greek alphabet (M, μ).
the consonant sound represented by this letter.
micron(def 1).

Origin of mu

First recorded in 1895–1900, mu is from the Greek word mŷ
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for m

Contemporary Examples of m

Historical Examples of m

  • The Syrians added to it an m, thus giving it a participial form.

  • There was the tram line, if m'sieur did not care to take a fiacre.

    The Black Bag

    Louis Joseph Vance

  • I can't keep my mind on m' fishing—just wondering what the deuce he's after.

    Good Indian

    B. M. Bower

  • We-e-ell, yuh see, m' son, it's my business to mind other people's business!

    Good Indian

    B. M. Bower

  • "You're across the dead line, m' son," said Stanley, with lazy significance.

    Good Indian

    B. M. Bower

British Dictionary definitions for m

m

M

noun plural m's, M's or Ms

the 13th letter and tenth consonant of the modern English alphabet
a speech sound represented by this letter, usually a bilabial nasal, as in mat

m

symbol for

metre(s)
mile(s)
milli-
minute(s)

M

symbol for

mach
medium (size)
mega-
currency mark(s)
million
astronomy Messier catalogue; a catalogue published in 1784, in which 103 nebulae and clusters are listed using a numerical systemM13 is the globular cluster in Hercules
Middle
physics modulus
(in Britain) motorwaythe M1 runs from London to Leeds
(in Australia)
  1. mature audience (used to describe a category of film certified as suitable for viewing by anyone over the age of 15)
  2. (as modifier)an M film
logic the middle term of a syllogism
physics mutual inductance
chem molar
(Roman numeral) 1000See Roman numerals

abbreviation for

Malta (international car registration)

m-

prefix

short for meta- (def. 4)

m-

prefix

indicating the use of mobile-communications technologym-banking

m.

abbreviation for

cricket maiden (over)
male
mare
married
masculine

M.

abbreviation for

Majesty
(in titles) Member
million
Also: M plural MM or MM French Monsieur
mountain

Word Origin for M.

sense 4) French equivalent of Mr

M'-

prefix

a variant of Mac-

'm

contraction of

(verb) am
(noun) madamyes'm

Mc-

prefix

a variant of Mac-

usage

For names beginning with this prefix, see under Mac-

mu

1

noun

the 12th letter in the Greek alphabet (Μ, μ), a consonant, transliterated as m

mu

2

the internet domain name for

Mauritius

MU

abbreviation for

Musicians' Union

Mac-

Mc- or M'-

prefix

(in surnames of Scottish or Irish Gaelic origin) son ofMacDonald; MacNeice

Word Origin for Mac-

from Goidelic mac son of; compare Welsh mab, Cornish mab
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for m

M

13th letter, from Greek mu, from Semitic mem. The Roman symbol for 1,000; sometimes used in this sense in English 15c.-16c.; but in late 20c. newspaper headlines it stands for million. As a thickness of type, from 1680s.

Mac-

common element in Scottish and Irish names, from Old Celtic *makko-s "son." Cognate root *makwos "son" produced Old Welsh map, Welsh mab, ap "son;" also probably cognate with Old English mago "son, attendant, servant," Old Norse mögr "son," Gothic magus "boy, servant," Old English mægð "maid" (see maiden).

Online Etymology Dictionary, © 2010 Douglas Harper
m in Medicine

m

abbr.

mass
meter

M

abbr.

molar1
molarity
morgan
myopia

m-

abbr.

meta-

mu

[myōō, mōō]

n.

The 12th letter of the Greek alphabet.

adj.

Of, relating to, or being a polypeptide chain that is one of five types of heavy chains present in immunoglobins.

Mu

abbr.

Mache unit
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
m in Science

m

Abbreviation of mass, meter
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.