genus Chamaemelum vs Compositae

genus Chamaemelum and Compositae both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Chamaemelum	Yes	No	No	No
Compositae	Yes	No	No	No

genus Chamaemelum (noun)	Compositae (noun)
small genus of plants sometimes included in genus Anthemis: chamomile	plants with heads composed of many florets: aster, daisy, dandelion, goldenrod, marigold, lettuces, ragweed, sunflower, thistle, zinnia