genus Parthenium vs Compositae

genus Parthenium and Compositae both are nouns.

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

genus Parthenium (noun)	Compositae (noun)
small genus of North American herbs and shrubs with terminal panicles of small ray flowers	plants with heads composed of many florets: aster, daisy, dandelion, goldenrod, marigold, lettuces, ragweed, sunflower, thistle, zinnia