aroma vs smell

aroma and smell both are nouns.

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

As nouns, aroma and smell are synonyms defined as:

Other synonyms of aroma include odor, odour, olfactory property, scent.

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

aroma: a distinctive odor that is pleasant
smell: the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form

Other hypernyms of aroma include odor, odour, olfactory perception, olfactory sensation.

aroma (noun)	smell (noun)
any property detected by the olfactory system	the act of perceiving the odor of something
a distinctive odor that is pleasant	any property detected by the olfactory system
	the faculty that enables us to distinguish scents
	the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form
	the general atmosphere of a place or situation and the effect that it has on people

aroma (verb)	smell (verb)
	become aware of not through the senses but instinctively
	emit an odor
	inhale the odor of; perceive by the olfactory sense
	smell bad
	have an element suggestive (of something)