stimulant vs excitant

stimulant and excitant both are nouns.

Word	Noun	Adjective	Verb	Adverb
stimulant	Yes	Yes	No	No
excitant	Yes	Yes	No	No

As nouns, stimulant and excitant are synonyms defined as:

stimulant and excitant: a drug that temporarily quickens some vital process

Other synonyms of stimulant include stimulant drug.

stimulant (noun)	excitant (noun)
a drug that temporarily quickens some vital process	a drug that temporarily quickens some vital process
any stimulating information or event; acts to arouse action

stimulant (adjective)	excitant (adjective)
that stimulates	(of drugs e.g.) able to excite or stimulate