Sebastiana vs rosid dicot genus

Sebastiana and rosid dicot genus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sebastiana	Yes	No	No	No
rosid dicot genus	Yes	No	No	No

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

Sebastiana (noun)	rosid dicot genus (noun)
Mexican spurges	a genus of dicotyledonous plants