Unitarianism vs religion

Unitarianism and religion both are nouns.

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

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

Unitarianism: a non-doctrinal religion that stresses individual freedom of belief and rejects the Trinity
religion: a strong belief in a supernatural power or powers that control human destiny

Other hypernyms of Unitarianism include faith, religious belief.

Unitarianism (noun)	religion (noun)
a non-doctrinal religion that stresses individual freedom of belief and rejects the Trinity	a strong belief in a supernatural power or powers that control human destiny
	an institution to express belief in a divine power