bog aster vs aster

bog aster and aster both are nouns.

Word	Noun	Adjective	Verb	Adverb
bog aster	Yes	No	No	No
aster	Yes	No	No	No

As nouns, aster is a hypernym of bog aster; that is, aster is a word with a broader meaning than bog aster:

bog aster: a variety of aster (Oclemena nemoralis)
aster: any of various chiefly fall-blooming herbs of the genus Aster with showy daisylike flowers

bog aster (noun)	aster (noun)
a variety of aster (Oclemena nemoralis)	star-shaped structure formed in the cytoplasm of a cell having fibers like rays that surround the centrosome during mitosis
	any of various chiefly fall-blooming herbs of the genus Aster with showy daisylike flowers