pyracanth vs shrub

pyracanth and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
pyracanth	Yes	No	No	No
shrub	Yes	No	No	No

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

pyracanth: any of various thorny shrubs of the genus Pyracantha bearing small white flowers followed by hard red or orange-red berries
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of pyracanth include bush.

pyracanth (noun)	shrub (noun)
any of various thorny shrubs of the genus Pyracantha bearing small white flowers followed by hard red or orange-red berries	a low woody perennial plant usually having several major stems