1. an official system of principles or tenets concerning faith, morals, behavior, etc., as of a church. Synonyms: doctrine, teachings, set of beliefs, philosophy.
2. a specific tenet or doctrine authoritatively laid down, as by a church. Synonyms: tenet, canon, law.
3. prescribed doctrine proclaimed as unquestionably true by a particular group.
4. a settled or established opinion, belief, or principle. Synonyms: conviction, certainty.
5. Slang: a collection of established opinions which are not necessarily factual.
Etymology: Latin, from Greek, opinion, belief, from dokein, to seem, think; see.