Lactuca vs Compositae

Lactuca and Compositae both are nouns.

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

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