overexploit vs exploit

overexploit is not a noun while exploit is a noun.

Word	Noun	Adjective	Verb	Adverb
overexploit	No	No	Yes	No
exploit	Yes	No	Yes	No

As verbs, exploit is a hypernym of overexploit; that is, exploit is a word with a broader meaning than overexploit:

Other hypernyms of overexploit include tap.

overexploit (noun)	exploit (noun)
	a notable achievement

overexploit (verb)	exploit (verb)
exploit excessively	use or manipulate to one's advantage
	draw from; make good use of
	work excessively hard