Sub-religion

noun
1.
a set of beliefs concerning the cause, nature, and purpose of the universe, especially when considered as the creation of a superhuman agency or agencies, usually involving devotional and ritual observances, and often containing a moral code governing the conduct of human affairs.
2.
a specific fundamental set of beliefs and practices generally agreed upon by a number of persons or sects:
the Christian religion; the Buddhist religion.
3.
the body of persons adhering to a particular set of beliefs and practices:
a world council of religions.
4.
the life or state of a monk, nun, etc.:
to enter religion.
5.
the practice of religious beliefs; ritual observance of faith.
6.
something one believes in and follows devotedly; a point or matter of ethics or conscience:
to make a religion of fighting prejudice.
7.
religions, Archaic. religious rites:
painted priests performing religions deep into the night.
8.
Archaic. strict faithfulness; devotion:
a religion to one’s vow.
Idioms
9.
get religion, Informal.

to acquire a deep conviction of the validity of religious beliefs and practices.
to resolve to mend one’s errant ways:
The company got religion and stopped making dangerous products.

noun
1.
belief in, worship of, or obedience to a supernatural power or powers considered to be divine or to have control of human destiny
2.
any formal or institutionalized expression of such belief: the Christian religion
3.
the attitude and feeling of one who believes in a transcendent controlling power or powers
4.
(mainly RC Church) the way of life determined by the vows of poverty, chastity, and obedience entered upon by monks, friars, and nuns: to enter religion
5.
something of overwhelming importance to a person: football is his religion
6.
(archaic)

the practice of sacred ritual observances
sacred rites and ceremonies

religion
see: get religion