Open English Wordnet
Nouns
(n)principle, rulea basic generalization that is accepted as true and that can be used as a basis for reasoning or conduct“their principles of composition characterized all their works” (n)principlea rule or standard especially of good behavior“a man of principle”,
“he will not violate his principles” (n)principlea basic truth or law or assumption“the principles of democracy” (n)principle, rulea rule or law concerning a natural phenomenon or the function of a complex system“the principle of the conservation of mass”,
“the principle of jet propulsion”,
“the right-hand rule for inductive fields” (n)rationale, principle(law) an explanation of the fundamental reasons (especially an explanation of the working of some device in terms of laws of nature)“the rationale for capital punishment”,
“the principles of internal-combustion engines”