overuse vs employ

overuse and employ both are nouns.

Word	Noun	Adjective	Verb	Adverb
overuse	Yes	No	Yes	No
employ	Yes	No	Yes	No

As verbs, employ is a hypernym of overuse; that is, employ is a word with a broader meaning than overuse:

overuse: make use of too often or too extensively
employ: put into service; make work or employ for a particular purpose or for its inherent or natural purpose

Other hypernyms of overuse include apply, use, utilise, utilize.

overuse (noun)	employ (noun)
exploitation to the point of diminishing returns	the state of being employed or having a job

overuse (verb)	employ (verb)
make use of too often or too extensively	put into service; make work or employ for a particular purpose or for its inherent or natural purpose
	engage or hire for work