fish vs fishy

fish is a noun but fishy is not a noun.

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

fish (noun)	fishy (noun)
any of various mostly cold-blooded aquatic vertebrates usually having scales and breathing through gills
the flesh of fish used as food

fish (adjective)	fishy (adjective)
	of or relating to or resembling fish
	not as expected

fish (verb)	fishy (verb)
catch or try to catch fish or shellfish
seek indirectly