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

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
Recent Examples on the Web And in the elder Bork’s view, famously set out in his book, The Antitrust Paradox (1978), consumer welfare was (to oversimplify) the underlying principle that made sense of our antitrust law. Andrew Stuttaford, National Review, 7 May 2022 The entrepreneur behind Tesla and SpaceX has also made a point of asserting that free speech should be Twitter’s governing principle. Stephen Humphries, The Christian Science Monitor, 4 May 2022 This seems to be the Administration’s guiding legal principle. The Editorial Board, WSJ, 3 May 2022 Transparency is the basic principle to follow in such moments. Ari Rabin-havt, The New Republic, 28 Apr. 2022 This is an important principle that all government policy-makers could take to heart. Paul Hsieh, Forbes, 26 Apr. 2022 Blending into the natural environment was the core design principle for the Ritz-Carlton, Nikko. Travel + Leisure, 12 Apr. 2022 The universality of human nature — the equal dignity of us all that is the key principle of the American project — means that, freed from the shackles of oppression, all nations could live freely, peacefully, and prosperously. Shay Khatiri, The Week, 26 Mar. 2022 Both are the same basic principle of a wing both on top and bottom, but have a very different feel. Bella Cacciatore, Glamour, 18 Mar. 2022 See More

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.

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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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

12 May 2022

Cite this Entry

“Principle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/principle. Accessed 17 May. 2022.

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More Definitions for principle

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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