Dalmatian laburnum vs shrub

Dalmatian laburnum and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
Dalmatian laburnum	Yes	No	No	No
shrub	Yes	No	No	No

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

Dalmatian laburnum: erect shrub having large trifoliate leaves and dense clusters of yellow flowers followed by poisonous seeds; Yugoslavia; sometimes placed in genus Cytisus
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of Dalmatian laburnum include bush.

Dalmatian laburnum (noun)	shrub (noun)
erect shrub having large trifoliate leaves and dense clusters of yellow flowers followed by poisonous seeds; Yugoslavia; sometimes placed in genus Cytisus	a low woody perennial plant usually having several major stems