Viburnum trilobum vs shrub

Viburnum trilobum and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
Viburnum trilobum	Yes	No	No	No
shrub	Yes	No	No	No

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

Viburnum trilobum: deciduous North American shrub or small tree having three-lobed leaves and red berries
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of Viburnum trilobum include bush.

Viburnum trilobum (noun)	shrub (noun)
deciduous North American shrub or small tree having three-lobed leaves and red berries	a low woody perennial plant usually having several major stems