bullock heart vs bullock's heart

bullock heart and bullock's heart both are nouns.

Word	Noun	Adjective	Verb	Adverb
bullock heart	Yes	No	No	No
bullock's heart	Yes	No	No	No

As nouns, bullock heart and bullock's heart are synonyms defined as:

bullock heart and bullock's heart: small tropical American tree bearing a bristly heart-shaped acid tropical fruit

Other synonyms of bullock heart include Annona reticulata, bullock's heart tree.

bullock heart (noun)	bullock's heart (noun)
small tropical American tree bearing a bristly heart-shaped acid tropical fruit	large heart-shaped tropical fruit with soft acid pulp
	small tropical American tree bearing a bristly heart-shaped acid tropical fruit