sweat vs struggle

sweat and struggle both are nouns.

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

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

sweat (noun)	struggle (noun)
use of physical or mental energy; hard work	strenuous effort
salty fluid secreted by sweat glands	an energetic attempt to achieve something
condensation of moisture on a cold surface	an open clash between two opposing groups (or individuals)
agitation resulting from active worry

sweat (verb)	struggle (verb)
excrete perspiration through the pores in the skin	be engaged in a fight; carry on a fight
	to exert strenuous effort against opposition
	climb awkwardly, as if by scrambling
	make a strenuous or labored effort