Rhamnus vs dicot genus

Rhamnus and dicot genus both are nouns.

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

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

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

Other hypernyms of Rhamnus include magnoliopsid genus.

Rhamnus (noun)	dicot 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