Definitions and associations of rule of interest to psychologists include
- Rewrite rule, in generative grammar and computer science
- Standardization, a formal and widely-accepted statement, fact, definition, or qualification
- Operation, a determinate rule (method) for performing a mathematical operation and obtaining a certain result (Mathematics, Logic)
- Rule of inference, a function from sets of formulae to formulae (Mathematics, Logic)
- Rule of thumb, principle with broad application that is not intended to be strictly accurate or reliable for every situation. Also often simply referred to as a rule
- Moral, an atomic element of a moral code for guiding choices in human behavior
- Heuristic, a quantized "rule" which shows a tendency or probability for successful function
- Norm (sociology), an informal but widely accepted rule, concept, truth, definition, or qualification (social norms, legal norms, coding norms)
- Norm (philosophy), a kind of sentence or a reason to act, feel or believe