fish vs prawn

fish and prawn both are nouns.

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

As verbs, prawn is a hyponym of fish; that is, prawn is a word with a more specific, narrower meaning than fish:

Other hyponyms of fish include crab, seine, scallop, scollop, rail, brail, angle, shrimp, net fish, shark, trawl, still-fish.

fish (noun)	prawn (noun)
any of various mostly cold-blooded aquatic vertebrates usually having scales and breathing through gills	shrimp-like decapod crustacean having two pairs of pincers; most are edible
the flesh of fish used as food	any of various edible decapod crustaceans

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