bird's-eye bush vs shrub

bird's-eye bush and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird's-eye bush	Yes	No	No	No
shrub	Yes	No	No	No

As nouns, shrub is a hypernym of bird's-eye bush; that is, shrub is a word with a broader meaning than bird's-eye bush:

bird's-eye bush: shrub with narrow-elliptic glossy evergreen leaves and yellow flowers with leathery petaloid sepals
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of bird's-eye bush include bush.

bird's-eye bush (noun)	shrub (noun)
shrub with narrow-elliptic glossy evergreen leaves and yellow flowers with leathery petaloid sepals	a low woody perennial plant usually having several major stems