Faith (noun)

1. A belief in or acceptance of something that is not based on proof.
2. A system of religious belief.
3. The trust or confidence in something or someone.
4. The belief in the existence of a god or gods.
5. The state of being loyal or devoted to someone or something.

Origin:

Old english fǣth, of germanic origin; related to dutch geloof and german glaube.

Examples:

1. She had faith in her abilities.
2. He has faith in God.
3. The company's success is built on the faith of its customers.
4. The religion is based on faith.
5. She had faith in her husband's innocence.