Definition of em
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
From the M-W Editors
13th Century
First Known Use of em
13th century
EM
abbreviation
Definition of EM
1 electromagnetic
2 electron microscope; electron microscopy
3 end matched
4 engineer of mines
5 enlisted man
Other Electrical Engineering Terms
EM- Defined for Kids
Medical Dictionary
EM
abbreviation
Medical Definition of EM
1electromagnetic
2electron microscope; electron microscopy
3emergency medicine
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