mimosa bush vs acacia

mimosa bush and acacia both are nouns.

Word	Noun	Adjective	Verb	Adverb
mimosa bush	Yes	No	No	No
acacia	Yes	No	No	No

As nouns, acacia is a hypernym of mimosa bush; that is, acacia is a word with a broader meaning than mimosa bush:

mimosa bush: tropical American thorny shrub or small tree; fragrant yellow flowers used in making perfumery
acacia: any of various spiny trees or shrubs of the genus Acacia

mimosa bush (noun)	acacia (noun)
tropical American thorny shrub or small tree; fragrant yellow flowers used in making perfumery	any of various spiny trees or shrubs of the genus Acacia