SINCE 1828
em
noun
\ 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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