bird feed vs feed

bird feed and feed both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird feed	Yes	No	No	No
feed	Yes	No	Yes	No

As nouns, feed is a hypernym of bird feed; that is, feed is a word with a broader meaning than bird feed:

Other hypernyms of bird feed include provender.

bird feed (noun)	feed (noun)
food given to birds; usually mixed seeds	food for domestic livestock

bird feed (verb)	feed (verb)
	provide with fertilizers or add nutrients to
	introduce continuously
	take in food; used of animals only
	give food to
	serve as food for; be the food for
	feed into; supply
	provide as food
	gratify
	profit from in an exploitatory manner
	move along, of liquids
	support or promote