bouquet vs aroma

bouquet and aroma both are nouns.

Word	Noun	Adjective	Verb	Adverb
bouquet	Yes	No	No	No
aroma	Yes	No	No	No

As nouns, aroma is a hypernym of bouquet; that is, aroma is a word with a broader meaning than bouquet:

Other hypernyms of bouquet include odor, odour, olfactory property, scent, smell.

bouquet (noun)	aroma (noun)
an arrangement of flowers that is usually given as a present	any property detected by the olfactory system
a pleasingly sweet olfactory property	a distinctive odor that is pleasant