witch hazel vs shrub

witch hazel and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
witch hazel	Yes	No	No	No
shrub	Yes	No	No	No

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

witch hazel: any of several shrubs or trees of the genus Hamamelis; bark yields an astringent lotion
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of witch hazel include bush.

witch hazel (noun)	shrub (noun)
lotion consisting of an astringent alcoholic solution containing an extract from the witch hazel plant	a low woody perennial plant usually having several major stems
any of several shrubs or trees of the genus Hamamelis; bark yields an astringent lotion