Rhamnus vs magnoliopsid genus

Rhamnus and magnoliopsid genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rhamnus	Yes	No	No	No
magnoliopsid genus	Yes	No	No	No

As nouns, magnoliopsid genus is a hypernym of Rhamnus; that is, magnoliopsid genus is a word with a broader meaning than Rhamnus:

Rhamnus: type genus of the Rhamnaceae: buckthorns
magnoliopsid genus: genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination

Other hypernyms of Rhamnus include dicot genus.

Rhamnus (noun)	magnoliopsid genus (noun)
type genus of the Rhamnaceae: buckthorns	genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination