1. The mental act, condition, or habit of placing trust or confidence in another person: Monroe's belief in Zola's honesty is as strong as ever.
2. Mental acceptance of and conviction in the truth, actuality, or validity of something: It is Harvey's belief that it will rain in the evening because he could see dark clouds overhead.
3. Something that is accepted as true; especially, a particular tenet or a body of tenets or teachings that are accepted by a group of people: The beliefs of the union members are stated in the contract and bylaws.
4. A statement, principle, or doctrine that a person or group accepts as true; such as, religious principles: Nena's strong religious beliefs have been challenged by something that she read about some religious leaders in the newspaper.
5. Etymology: before 1400 belyefe, before 1225, it was bileve and probably before 1200, it is assumed to have been bileave.

The Old English geleafa is descended from the same language or form of Old Saxon gilobo, "belief", Old High German giloubo (modern German Glaube), and Gothic galaubeins, "belief" and galaubjan, "to believe".