four-o'clock family vs genus Allionia

four-o'clock family and genus Allionia both are nouns.

Word	Noun	Adjective	Verb	Adverb
four-o'clock family	Yes	No	No	No
genus Allionia	Yes	No	No	No

four-o'clock family (noun)	genus Allionia (noun)
a family of flowering plants of the order Caryophyllales	small genus of chiefly American herbs