sweet gale vs shrub

sweet gale and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet gale	Yes	No	No	No
shrub	Yes	No	No	No

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

sweet gale: bog shrub of north temperate zone having bitter-tasting fragrant leaves
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of sweet gale include bush.

sweet gale (noun)	shrub (noun)
bog shrub of north temperate zone having bitter-tasting fragrant leaves	a low woody perennial plant usually having several major stems