Ruscus aculeatus vs shrub

Ruscus aculeatus and shrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ruscus aculeatus	Yes	No	No	No
shrub	Yes	No	No	No

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

Ruscus aculeatus: shrub with stiff flattened stems resembling leaves (cladophylls); used for making brooms
shrub: a low woody perennial plant usually having several major stems

Other hypernyms of Ruscus aculeatus include bush.

Ruscus aculeatus (noun)	shrub (noun)
shrub with stiff flattened stems resembling leaves (cladophylls); used for making brooms	a low woody perennial plant usually having several major stems