SynonymDefinitionAntonym.com - English Synonym Dictionary

A basic truth or law or assumption

A rule or standard especially of good behavior

(law) an explanation of the fundamental reasons (especially an explanation of the working of some device in terms of laws of nature)

A basic generalization that is accepted as true and that can be used as a basis for reasoning or conduct

A rule or law concerning a natural phenomenon or the function of a complex system

Rule of personal conduct