paganism vs religion

paganism and religion both are nouns.

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

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

paganism: any of various religions other than Christianity or Judaism or Islamism
religion: a strong belief in a supernatural power or powers that control human destiny

Other hypernyms of paganism include faith, religious belief.

paganism (noun)	religion (noun)
any of various religions other than Christianity or Judaism or Islamism	a strong belief in a supernatural power or powers that control human destiny
	an institution to express belief in a divine power