macadamia nut tree vs macadamia

macadamia nut tree and macadamia both are nouns.

Word	Noun	Adjective	Verb	Adverb
macadamia nut tree	Yes	No	No	No
macadamia	Yes	No	No	No

As nouns, macadamia is a hypernym of macadamia nut tree; that is, macadamia is a word with a broader meaning than macadamia nut tree:

macadamia nut tree: small Australian tree with racemes of pink flowers; widely cultivated (especially in Hawaii) for its sweet edible nuts
macadamia: any tree of the genus Macadamia

Other hypernyms of macadamia nut tree include macadamia tree.

macadamia nut tree (noun)	macadamia (noun)
small Australian tree with racemes of pink flowers; widely cultivated (especially in Hawaii) for its sweet edible nuts	any tree of the genus Macadamia