khat vs excitant

khat and excitant both are nouns.

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

As nouns, excitant is a hypernym of khat; that is, excitant is a word with a broader meaning than khat:

khat: the leaves of the shrub Catha edulis which are chewed like tobacco or used to make tea; has the effect of a euphoric stimulant
excitant: a drug that temporarily quickens some vital process

Other hypernyms of khat include stimulant, stimulant drug.

khat (noun)	excitant (noun)
the leaves of the shrub Catha edulis which are chewed like tobacco or used to make tea; has the effect of a euphoric stimulant	a drug that temporarily quickens some vital process

khat (adjective)	excitant (adjective)
	(of drugs e.g.) able to excite or stimulate