thorn apple vs shrub

thorn apple and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
thorn apple	Yes	No	No	No
shrub	Yes	No	No	No

As nouns, shrub is a hypernym of thorn apple; that is, shrub is a word with a broader meaning than thorn apple:

Other hypernyms of thorn apple include bush.

thorn apple (noun)	shrub (noun)
any of several plants of the genus Datura	a low woody perennial plant usually having several major stems