theism vs religion

theism and religion both are nouns.

Word	Noun	Adjective	Verb	Adverb
theism	Yes	No	No	No
religion	Yes	No	No	No

As nouns, religion is a hypernym of theism; that is, religion is a word with a broader meaning than theism:

theism: the doctrine or belief in the existence of a God or gods
religion: a strong belief in a supernatural power or powers that control human destiny

Other hypernyms of theism include faith, religious belief.

theism (noun)	religion (noun)
the doctrine or belief in the existence of a God or gods	a strong belief in a supernatural power or powers that control human destiny
	an institution to express belief in a divine power