\ 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

Both note that theorists modeling galaxy evolution must still rely on approximate models of star formation, which lie at the crux of the issue. Adrian Cho, Science | AAAS, "Galaxy hunters spot hidden giants in the early universe," 7 Aug. 2019 The spacecraft, whose stainless steel design Musk explained in an interview with Popular Mechanics, is at the crux of the company's future plans. David Grossman, Popular Mechanics, "SpaceX Successfully Tests Hopper Prototype," 26 July 2019 According to Mattocks, who's scored twice this year, that's at the crux of the problem. Pat Brennan,, "FC Cincinnati's offense: Why can't they score more?," 23 July 2019 The contention that a car backfired was at the crux of the trial of former Cleveland police officer Michael Brelo, who was acquitted in 2015 of voluntary manslaughter charges in the shooting deaths of Williams and Russell. Evan Macdonald,, "Trial for Cleveland police supervisor charged in 2012 chase hinges on responsibility for subordinates’ actions, attorneys say," 15 July 2019 The benefits of a breakup The crux of it is that Google’s core search business is so profitable that the rest of Alphabet’s many subsidiaries are freeloading off it. Adam Seessel, Fortune, "Valuation: I’m a Google Shareholder. Here’s Why I Think More Regulation Would Be Good for Google," 26 July 2019 The crux of the investigation was to figure out whether the employees violated the department’s internet policy, which applies to employees’ personal websites, videos and all forms of social media. Lisa Maria Garza,, "Lake County Sheriff’s Office clears 16 employees for ‘offensive’ posts exposed by Plain View Project," 25 July 2019 The question is whether the crux of the government’s explanation for ditching DACA—the purported illegality of the programme—is plausible and defensible under the APA. S.m. | New York, The Economist, "What to expect when DACA arrives at the Supreme Court," 24 July 2019 The crux of the problem, as Red Sox pitching analyst Brian Bannister recently noted, has been the team’s poor performance with runners in scoring position. Alex Speier,, "Breaking down a bizarre first half for the Red Sox," 10 July 2019

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

14 Aug 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).


to move or obtain by small maneuvers

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