megacycle vs megahertz

megacycle and megahertz both are nouns.

Word	Noun	Adjective	Verb	Adverb
megacycle	Yes	No	No	No
megahertz	Yes	No	No	No

As nouns, megacycle and megahertz are synonyms defined as:

Other synonyms of megacycle include Mc, megacycle per second, MHz.

megacycle (noun)	megahertz (noun)
one million periods per second	one million periods per second