- The definition of a principle is a basic truth or the source or origin of something or someone.
An example of principle is a list of values set by a group of people.
- the ultimate source, origin, or cause of something
- a natural or original tendency, faculty, or endowment
- a fundamental truth, law, doctrine, or motivating force, upon which others are based: moral principles
- a rule of conduct, esp. of right conduct
- such rules collectively
- adherence to them; integrity; uprightness: a man of principle
- an essential element, constituent, or quality, esp. one that produces a specific effect: the active principle of a medicine
- the scientific law that explains a natural action: the principle of cell division
- the method of a thing's operation: the principle of a gasoline engine is internal combustion
Origin of principleMiddle English altered ; from Middle French principe ; from Classical Latin principium: see principium
- A basic truth, law, or assumption: the principles of democracy.
- a. A rule or standard, especially of good behavior: a man of principle.b. The collectivity of moral or ethical standards or judgments: a decision based on principle rather than expediency.
- A fixed or predetermined policy or mode of action.
- A basic or essential quality or element determining intrinsic nature or characteristic behavior: the principle of self-preservation.
- A rule or law concerning the functioning of natural phenomena or mechanical processes: the principle of jet propulsion.
- Chemistry One of the elements that compose a substance, especially one that gives some special quality or effect.
- A basic source. See Usage Note at principal.
Origin of principleMiddle English, alteration of Old French principe, from Latin prīncipium, from prīnceps, prīncip-, leader, emperor; see per1 in Indo-European roots.
- A fundamental assumption.
- We need some sort of principles to reason from.
- A rule used to choose among solutions to a problem.
- The principle of least privilege holds that a process should only receive the permissions it needs.
- (usually in the plural) Moral rule or aspect.
- I don't doubt your principles; you are clearly a person of principle. It's the principle of the thing; I won't do business with someone I can't trust.
- (physics) A rule or law of nature, or the basic idea on how the laws of nature are applied.
- Bernoulli's principle; The Pauli Exclusion Principle prevents two fermions from occupying the same state. The principle of the internal combustion engine
- A fundamental essence, particularly one producing a given quality.
- Many believe that life is the result of some vital principle.
- A source, or origin; that from which anything proceeds; fundamental substance or energy; primordial substance; ultimate element, or cause.
- An original faculty or endowment.
Principle is always a noun ("moral rule"), but it is often confused with principal, which can be an adjective ("most important") or a noun ("school principal"). Consult both definitions if in doubt.
- He is the principle musician in the band
- She worked ten years as school principle
A mnemonic to avoid this confusion is "The principal alphabetic principle places A before E".
(third-person singular simple present principles, present participle principling, simple past and past participle principled)