Translate principle | into French | into German | into Italian | into Spanish Definition of principle
noun
1a fundamental truth or proposition that serves as the foundation for a system of belief or behavior or for a chain of reasoning:the basic principles of Christianity (usually
principles)
a rule or belief governing one’s personal behavior:struggling to be true to their own principles she resigned over a matter of principle morally correct behavior and attitudes:a man of principle a general scientific theorem or law that has numerous special applications across a wide field. a natural law forming the basis for the construction or working of a machine:these machines all operate on the same general principle
2a fundamental source or basis of something:the first principle of all things was water a fundamental quality or attribute determining the nature of something; an essence:the combination of male and female principles [with adjective] Chemistry an active or characteristic constituent of a substance, obtained by simple analysis or separation:the active principle in the medulla is epinephrine
