EMabbr.1. electromagnetic2. Engineer of Mines3. enlisted manem (?m)n.1. The letter m.2. Printing a. The width of a square or nearly square piece of type, used as a unit of measure for matter set in that size of type.b. Such a measure for 12-point type; a pica.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.em (?m) n1. (Printing, Lithography & Bookbinding) Also called: mutton or mut the square of a body of any size of type, used as a unit of measurement2. (Printing, Lithography & Bookbinding) Also called: pica em or pica a unit of measurement used in printing, equal to one sixth of an inch[C19: from the name of the letter M]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014em (?m) n., pl. ems. 1. the letter M, m. 2. the square of any size of type used as the unit of measurement for matter printed in that type size. [1860?65] EM 1. electromagnetic. 2. Engineer of Mines. 3. enlisted man or men. ’em (?m) pron. Informal. them. [1350?1400; Middle English hem, Old English heom, dat. and acc. pl. of he1] em-1 , var. of en- 1 before b, p, and sometimes m: embalm. Compare im- 1. em-2 , var. of en- 2 before b, m, p, ph: embolism; emphasis. E.M. Engineer of Mines. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.