Echium vs plant genus

Echium and plant genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Echium	Yes	No	No	No
plant genus	Yes	No	No	No

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

Echium (noun)	plant genus (noun)
a genus of bristly herbs and shrubs of the family Boraginaceae	a genus of plants