family Compositae vs genus Lactuca

family Compositae and genus Lactuca both are nouns.

Word	Noun	Adjective	Verb	Adverb
family Compositae	Yes	No	No	No
genus Lactuca	Yes	No	No	No

family Compositae (noun)	genus Lactuca (noun)
plants with heads composed of many florets: aster, daisy, dandelion, goldenrod, marigold, lettuces, ragweed, sunflower, thistle, zinnia	an herb with milky juice: lettuce; prickly lettuce