sweet gum tree vs sweet gum

sweet gum tree and sweet gum both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet gum tree	Yes	No	No	No
sweet gum	Yes	No	No	No

As nouns, sweet gum tree and sweet gum are synonyms defined as:

sweet gum tree and sweet gum: a North American tree of the genus Liquidambar having prickly spherical fruit clusters and fragrant sap

Other synonyms of sweet gum tree include American sweet gum, bilsted, Liquidambar styraciflua, red gum.

sweet gum tree (noun)	sweet gum (noun)
a North American tree of the genus Liquidambar having prickly spherical fruit clusters and fragrant sap	a North American tree of the genus Liquidambar having prickly spherical fruit clusters and fragrant sap
	aromatic exudate from the sweet gum tree
	reddish-brown wood and lumber from heartwood of the sweet gum tree used to make furniture