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\ ˈem 
\
\Definition of em
(Entry 1 of 3)
1 : the letter m
2 : the width of a piece of type about as wide as it is tall used as a unit of measure of typeset matter
EM
abbreviationDefinition of EM (Entry 2 of 3)
1 electromagnetic
2 electron microscope; electron microscopy
3 end matched
4 engineer of mines
5 enlisted man
em-
prefixDefinition of em- (Entry 3 of 3)
— see en-
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Time Traveler for em
The first known use of em was in the 13th century
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