mc has definitions from the field of physics
1
[ noun ] (physics) one million periods per second

Used in print

(Walter H. Buchsbaum, "Advances in Medical Electronics"...)

The frequency used for these experiments is 15 mc. and the transducer is a specially cut crystal with an epoxy lens capable of providing beam diameters smaller than one millimeter .

Related terms

rate kilohertz

2
[ noun ] Last name, frequency rank in the U.S. is 29994
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