principle

noun
prin·​ci·​ple | \ ˈprin(t)-s(ə-)pəl How to pronounce principle (audio) , -sə-bəl \

Definition of principle

1a : a comprehensive and fundamental law, doctrine, or assumption
b(1) : a rule or code of conduct
(2) : habitual devotion to right principles a man of principle
c : the laws or facts of nature underlying the working of an artificial device
2 : a primary source : origin
3a : an underlying faculty or endowment such principles of human nature as greed and curiosity
b : an ingredient (such as a chemical) that exhibits or imparts a characteristic quality
4 capitalized, Christian Science : a divine principle : god
in principle
: with respect to fundamentals prepared to accept the proposition in principle

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Principle vs. Principal: Usage Guide

Evidence of confusion between principle and principal can be found even in publications overseen by professional editors. To keep these words straight, remember that principle functions only as a noun, and in its most common uses refers to a basic rule or law, as in a guiding principle or a matter of principle. If you are looking for an adjective form of this word, you must use principled, as in taking a principled stand. Principal functions as both a noun and an adjective. The noun has various meanings referring to someone with controlling authority the school principal or in a leading position the ballet's two principals , but also has meanings relating to finance, law, and architecture. As an adjective, principal typically means "most important," as in the principal reason.

Examples of principle in a Sentence

Urban guerrilla warfare was futile against a thermonuclear superstate that would stop at nothing to defend the profit principle. — Philip Roth, American Pastoral, 1997 Better, of course, to take a higher road, operate on the principle of service and see if things don't turn out better … — Richard Ford, Independence Day, 1995 Pointlessness was life's principle, and it spread its sadness. — Arthur Miller, Timebends, 1987 His investment strategy is based on the principle that the stock market offers the best returns for long-term investors. the basic principles of hydraulics
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Recent Examples on the Web Robert Cialdini discussed this principle and its mechanisms in his book Influence: The Psychology of Persuasion. James O'connor, Forbes, 2 Sep. 2021 For almost six decades, Watts, who died on Tuesday at 80, lived this principle as the less visible heart and soul of the Rolling Stones. BostonGlobe.com, 25 Aug. 2021 Therefore, the American people deserve to know the extent to which their government is using Big Tech to violate this basic constitutional principle and do what the Constitution forbids of it. Bill Hagerty, National Review, 29 July 2021 The nation was built on this principle of equality, and Americans of all political perspectives must live it. Michael K. Gusmano, Scientific American, 22 July 2021 Indeed, the Civil Service in the UK operated on this principle until 2019 but used a 25% top performer quota. Bogdan Costea, Quartz, 5 July 2021 This principle ostensibly prevented any one party from exercising monopoly control over natural resources. The Salt Lake Tribune, 13 June 2021 Follow this principle and your suit will do the talking. Roxanne Adamiyatt, Town & Country, 9 June 2021 So, my fear is that these people are going to walk out of principle. Kayla Rivas, Fox News, 24 Aug. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'principle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of principle

14th century, in the meaning defined at sense 1a

History and Etymology for principle

Middle English, from Middle French principe, principle, from Old French, from Latin principium beginning, from princip-, princeps initiator — more at prince

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Learn More About principle

Time Traveler for principle

Time Traveler

The first known use of principle was in the 14th century

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Dictionary Entries Near principle

principium

principle

principled

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Statistics for principle

Last Updated

9 Sep 2021

Cite this Entry

“Principle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/principle. Accessed 15 Sep. 2021.

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More Definitions for principle

principle

noun

English Language Learners Definition of principle

: a moral rule or belief that helps you know what is right and wrong and that influences your actions
: a basic truth or theory : an idea that forms the basis of something
: a law or fact of nature that explains how something works or why something happens

principle

noun
prin·​ci·​ple | \ ˈprin-sə-pəl How to pronounce principle (audio) \

Kids Definition of principle

1 : a general or basic truth on which other truths or theories can be based scientific principles
2 : a rule of conduct based on beliefs of what is right and wrong
3 : a law or fact of nature which makes possible the working of a machine or device the principle of magnetism

principle

noun
prin·​ci·​ple | \ ˈprin(t)-sə-pəl How to pronounce principle (audio) \

Medical Definition of principle

1 : a comprehensive and fundamental law, doctrine, or assumption
2 : an ingredient (as a chemical) that exhibits or imparts a characteristic quality the active principle of a drug

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