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

Although nearly every handbook and many dictionaries warn against confusing principle and principal, many people still do. Principle is only a noun; principal is both adjective and noun. If you are unsure which noun you want, read the definitions in this dictionary.

Principle vs. Principal

Yes, these two words are confusing; we see evidence of the misuse of both in newspapers and books which have been overseen by professional editors, so don’t feel bad if you have trouble with them. Principle only functions as a noun (such as “a comprehensive and fundamental law, doctrine, or assumption”); if you want it to be an adjective you must use the word principled. Principal, on the other hand, may function as a noun (such as the head of a school) or as an adjective (meaning “most important”). 

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 The pandemic has forced EU regulators into a political balancing act between preserving member states’ jurisdiction over health policy and protecting the bloc’s principle of free movement. Nikos Chrysoloras, Bloomberg.com, "New EU Travel Plan Could Bring Clarity, Relief for Airlines," 5 Oct. 2020 As one person put it, many agreed with the blog post’s principle of work as a refuge from outside political strife. Gregory Barber, Wired, "The Turmoil Over ‘Black Lives Matter’ and Political Speech at Coinbase," 5 Oct. 2020 That powerful principle of the First Amendment applies here. Dean Baquet, New York Times, "An Editor’s Note on the Trump Tax Investigation," 27 Sep. 2020 If the court was enlarged to follow that principle, there would be 11 seats on the court. Grace Segers, CBS News, "Democrats eye expanding Supreme Court if Trump's nominee is confirmed," 25 Sep. 2020 Sharp applies that principle in his paying gig, as well. al, "Madison County, Guntersville looking forward to non-region challenge," 24 Sep. 2020 Cameron cited that principle in explaining his rationale Wednesday, saying he was bound to follow the law and the facts. Washington Post, "With Breonna Taylor decision, summer’s anguished protests get fresh impetus for the fall," 24 Sep. 2020 Now, with Republicans in control of the White House and the Senate, Democrats are wondering whether that principle will still hold. Haley Victory Smith, Washington Examiner, "Ginsburg told granddaughter before death she wished not to be replaced 'until a new president is installed'," 18 Sep. 2020 In line with that principle, the top job at the WTO is not sewn up for a European or an American, unlike those at the IMF or the World Bank. The Economist, "Global trade The race to lead the WTO begins," 11 July 2020

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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Statistics for principle

Last Updated

14 Oct 2020

Cite this Entry

“Principle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/principle. Accessed 25 Oct. 2020.

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More Definitions for principle

principle

noun
How to pronounce principle (audio)

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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Comments on principle

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