ground bait vs decoy

ground bait and decoy both are nouns.

Word	Noun	Adjective	Verb	Adverb
ground bait	Yes	No	No	No
decoy	Yes	No	Yes	No

As nouns, decoy is a hypernym of ground bait; that is, decoy is a word with a broader meaning than ground bait:

ground bait: bait scattered on the water to attract fish
decoy: something used to lure fish or other animals into danger so they can be trapped or killed

Other hypernyms of ground bait include bait, lure.

ground bait (noun)	decoy (noun)
bait scattered on the water to attract fish	something used to lure fish or other animals into danger so they can be trapped or killed
	a beguiler who leads someone into danger (usually as part of a plot)

ground bait (verb)	decoy (verb)
	lure or entrap with or as if with a decoy