shrimp vs fish

shrimp and fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
shrimp	Yes	No	Yes	No
fish	Yes	No	Yes	No

As verbs, fish is a hypernym of shrimp; that is, fish is a word with a broader meaning than shrimp:

shrimp (noun)	fish (noun)
small slender-bodied chiefly marine decapod crustaceans with a long tail and single pair of pincers; many species are edible	any of various mostly cold-blooded aquatic vertebrates usually having scales and breathing through gills
any of various edible decapod crustaceans	the flesh of fish used as food
disparaging terms for small people

shrimp (verb)	fish (verb)
fish for shrimp	catch or try to catch fish or shellfish
	seek indirectly