bitterwood vs bitterwood tree

bitterwood and bitterwood tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
bitterwood	Yes	No	No	No
bitterwood tree	Yes	No	No	No

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

bitterwood: handsome South American shrub or small tree having bright scarlet flowers and yielding a valuable fine-grained yellowish wood; yields the bitter drug quassia from its wood and bark
bitterwood tree: any of various trees or shrubs of the family Simaroubaceae having wood and bark with a bitter taste

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

bitterwood: West Indian tree yielding the drug Jamaica quassia
bitterwood tree: any of various trees or shrubs of the family Simaroubaceae having wood and bark with a bitter taste

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

bitterwood: medium to large tree of tropical North and South America having odd-pinnate leaves and long panicles of small pale yellow flowers followed by scarlet fruits
bitterwood tree: any of various trees or shrubs of the family Simaroubaceae having wood and bark with a bitter taste

bitterwood (noun)	bitterwood tree (noun)
handsome South American shrub or small tree having bright scarlet flowers and yielding a valuable fine-grained yellowish wood; yields the bitter drug quassia from its wood and bark	any of various trees or shrubs of the family Simaroubaceae having wood and bark with a bitter taste
West Indian tree yielding the drug Jamaica quassia
medium to large tree of tropical North and South America having odd-pinnate leaves and long panicles of small pale yellow flowers followed by scarlet fruits