postulant vs suppliant

postulant and suppliant both are nouns.

Word	Noun	Adjective	Verb	Adverb
postulant	Yes	No	No	No
suppliant	Yes	Yes	No	No

As nouns, suppliant is a hypernym of postulant; that is, suppliant is a word with a broader meaning than postulant:

postulant: one submitting a request or application especially one seeking admission into a religious order
suppliant: one praying humbly for something

Other hypernyms of postulant include petitioner, requester, supplicant.

postulant (noun)	suppliant (noun)
one submitting a request or application especially one seeking admission into a religious order	one praying humbly for something

postulant (adjective)	suppliant (adjective)
	humbly entreating