Saivism vs religion

Saivism and religion both are nouns.

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

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

Saivism: organized worship of the Indian god Shiva and one of the three principal forms of modern Hinduism.
religion: a strong belief in a supernatural power or powers that control human destiny

Other hypernyms of Saivism include faith, religious belief.

Saivism (noun)	religion (noun)
organized worship of the Indian god Shiva and one of the three principal forms of modern Hinduism.	a strong belief in a supernatural power or powers that control human destiny
	an institution to express belief in a divine power