/prin"seuh peuhl/, n.1. an accepted or professed rule of action or conduct: a person of good moral principles.2. a fundamental, primary, or general law or truth from which others are derived: the principles of modern physics.3. a fundamental doctrine or tenet; a distinctive ruling opinion: the principles of the Stoics.4. principles, a personal or specific basis of conduct or management: to adhere to one's principles; a kindergarten run on modern principles.5. guiding sense of the requirements and obligations of right conduct: a person of principle.6. an adopted rule or method for application in action: a working principle for general use.7. a rule or law exemplified in natural phenomena, the construction or operation of a machine, the working of a system, or the like: the principle of capillary attraction.8. the method of formation, operation, or procedure exhibited in a given case: a community organized on the patriarchal principle.9. a determining characteristic of something; essential quality.10. an originating or actuating agency or force: growth is the principle of life.11. an actuating agency in the mind or character, as an instinct, faculty, or natural tendency: the principles of human behavior.12. Chem. a constituent of a substance, esp. one giving to it some distinctive quality or effect.13. Obs. beginning or commencement.14. in principle, in essence or substance; fundamentally: to accept a plan in principle.15. on principle,a. according to personal rules for right conduct; as a matter of moral principle: He refused on principle to agree to the terms of the treaty.b. according to a fixed rule, method, or practice: He drank hot milk every night on principle.[1350-1400; ME, alter. of MF principe or L principium, on the analogy of MANCIPLE. See PRINCIPIUM]Syn. 1, 2, 3. PRINCIPLE, CANON, RULE imply something established as a standard or test, for measuring, regulating, or guiding conduct or practice. A PRINCIPLE is a general and fundamental truth that may be used in deciding conduct or choice: to adhere to principle.CANON, originally referring to an edict of the Church (a meaning that it still retains), is used of any principle, law, or critical standard that is officially approved, particularly in aesthetics and scholarship: canons of literary criticism.A RULE, usually something adopted or enacted, is often the specific application of a principle: the golden rule. 2. theorem, axiom, postulate, proposition. 5. integrity, probity, rectitude, honor.
* * *(as used in expressions)Archimedes' principleBernoulli's principleCopernican principleMach's principlePascal's principle
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