coral bush vs shrub

coral bush and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
coral bush	Yes	No	No	No
shrub	Yes	No	No	No

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

coral bush: Australian shrub having simple obovate leaves and brilliant scarlet flowers
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of coral bush include bush.

coral bush (noun)	shrub (noun)
Australian shrub having simple obovate leaves and brilliant scarlet flowers	a low woody perennial plant usually having several major stems