flounder vs struggle

flounder and struggle both are nouns.

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

As verbs, struggle is a hypernym of flounder; that is, struggle is a word with a broader meaning than flounder:

Other hypernyms of flounder include fight.

flounder (noun)	struggle (noun)
any of various European and non-European marine flatfish	strenuous effort
flesh of any of various American and European flatfish	an energetic attempt to achieve something
	an open clash between two opposing groups (or individuals)

flounder (verb)	struggle (verb)
walk with great difficulty	be engaged in a fight; carry on a fight
behave awkwardly; have difficulties	to exert strenuous effort against opposition
	climb awkwardly, as if by scrambling
	make a strenuous or labored effort