\ 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

Amen Corner, so named by Herbert Warren Wind, is the crux of the course, comprising, strictly speaking, the eleventh green, the twelfth hole, and the tee shot at thirteen. Nick Paumgarten, The New Yorker, "Inside the Cultish Dreamworld of Augusta National," 14 June 2019 The importance of seeking out and preserving these dishes is the crux of her book. Jenn Harris,, "Chicken Parm and spaghetti and meatballs are not real Italian food," 10 June 2019 This is the crux of one of the central problems in computer science. Quanta Magazine, "Computer Scientists Expand the Frontier of Verifiable Knowledge," 23 May 2019 This is crux of matter: can’t make system too annoying or people won’t use it, negatively affecting safety, but also can’t allow people to get too complacent or safety again suffers. David Grossman, Popular Mechanics, "Tesla Model 3 Autopilot Involved in Third Fatal Crash," 17 May 2019 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

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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Last Updated

19 Jun 2019

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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

Comments on crux

What made you want to look up crux? Please tell us where you read or heard it (including the quote, if possible).


incapable of being surmounted or overcome

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