sweat vs overexertion

sweat and overexertion both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweat	Yes	No	Yes	No
overexertion	Yes	No	No	No

As nouns, overexertion is a hyponym of sweat; that is, overexertion is a word with a more specific, narrower meaning than sweat:

sweat: use of physical or mental energy; hard work
overexertion: excessive exertion; so much exertion that discomfort or injury results

sweat (noun)	overexertion (noun)
use of physical or mental energy; hard work	excessive exertion; so much exertion that discomfort or injury results
salty fluid secreted by sweat glands
condensation of moisture on a cold surface
agitation resulting from active worry

sweat (verb)	overexertion (verb)
excrete perspiration through the pores in the skin