Rumex vs dicot genus

Rumex and dicot genus both are nouns.

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

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

Rumex: docks: coarse herbs and shrubs mainly native to north temperate regions
dicot genus: genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination

Other hypernyms of Rumex include magnoliopsid genus.

Rumex (noun)	dicot genus (noun)
docks: coarse herbs and shrubs mainly native to north temperate regions	genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination