\ ˈkrəks How to pronounce crux (audio) , ˈkru̇ks How to pronounce crux (audio) \
plural cruxes also cruces\ ˈkrü-​ˌsēz How to pronounce cruces (audio) \

Definition of crux

1 : a puzzling or difficult problem : an unsolved question The origin of the word is a scholarly crux.
2 : an essential point requiring resolution or resolving an outcome
3 : a main or central feature (as of an argument) … he discarded all but the essential cruxes of his argument.— Carl Van Doren

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Did You Know?

In Latin, crux referred literally to an instrument of torture, often a cross or stake, and figuratively to the torture and misery inflicted by means of such an instrument. Crux eventually developed the sense of "a puzzling or difficult problem"; that was the first meaning that was used when the word entered English in the early 18th century. Later, in the late 19th century, crux began to be used more specifically to refer to an essential point of a legal case that required resolution before the case as a whole could be resolved. Today, the verdict on crux is that it can be used to refer to any important part of a problem or argument, inside or outside of the courtroom.

Examples of crux in a Sentence

the crux of the problem is that the school's current budget is totally inadequate

Recent Examples on the Web

The crux of the matter revolves around Gruden taking his young quarterback’s game to the next level. Jarrett Bell, USA TODAY, "10 biggest questions for the 2018 NFL offseason," 5 Feb. 2018 Maurice also had complaints about what seems to be the crux of Green Book's plot: the evolution of the friendship between Don Shirley and Tony Vallelonga. Caroline Hallemann, Town & Country, "Don Shirley's Family Questions Green Book's Accuracy," 5 Jan. 2019 And that simple gesture is truly the crux of what makes Maddie and Millie’s friendship so great: The two are constantly in full support of the other, focusing on building each other up on their meteoric rise through young Hollywood. Lynsey Eidell, Teen Vogue, "Millie Bobby Brown and Maddie Ziegler Are BFF Goals at VMAs 2018," 21 Aug. 2018 But getting around cities and building interiors alike has aged very, very poorly, and this is the crux of the new compilation's problem. Sam Machkovech, Ars Technica, "Shenmue I & II impressions: A gaming history lesson, but it feels like school," 20 Aug. 2018 The pockmarked mass climbs high up the barren mountain valley–a blinding crux of snow, cloud, and sky. Daniel Otis, Sunset, "Awe-Inspiring Canadian Rockies Camping Adventure," 22 Jan. 2018 The crux of the problem is that women are looking for a different kind of underwear and a different set of values. Elizabeth Winkler, WSJ, "Victoria’s Secret: Sex Isn’t Selling," 17 Nov. 2018 The crux of his argument was built around Carlson’s decision to leave the department. Ben Guarino, The Verge, "An academic reported sexual harassment. Her university allegedly retaliated," 12 Nov. 2018 The crux of the decision, however, comes down to whether the Board of Land and Natural Resources had considered all the proper factors in making its decision to approve the latest agreement. John Timmer, Ars Technica, "Hawaiian Supreme Court gives go-ahead to giant telescope," 1 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'crux.' 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 crux

1718, in the meaning defined at sense 1

History and Etymology for crux

Latin cruc-, crux cross, torture

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Time Traveler for crux

The first known use of crux was in 1718

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More from Merriam-Webster on crux

Rhyming Dictionary: Words that rhyme with crux

Thesaurus: All synonyms and antonyms for crux

Spanish Central: Translation of crux

Nglish: Translation of crux for Spanish Speakers

Britannica English: Translation of crux for Arabic Speakers Encyclopedia article about crux

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