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definitions

m-

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

M-

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

Mac-

  1. 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

Mc-

2
  1. variant of Mac-.
Also Mc-.

M'-

  1. variant of Mac-.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for m-

m-

prefix
  1. short for meta- (def. 4)

m-

prefix
  1. indicating the use of mobile-communications technologym-banking

M'-

prefix
  1. a variant of Mac-

Mc-

prefix
  1. a variant of Mac-

usage

For names beginning with this prefix, see under Mac-

Mac-

Mc- or M'-

prefix
  1. (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-

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.
  1. meta-
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.