\ 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

Medical exemptions are at the crux of some of the most contentious arguments over how vaccination requirements should work, and more precisely who should be vaccinated in the first place. Carolyn L. Todd, SELF, "What Actually Counts as a Medical Exemption for Vaccines—and What's at Stake When They're Abused," 26 Aug. 2019 The administration’s rationale is the crux of battles over the question, which have morphed from confrontations in four courts to a fierce partisan struggle with potentially huge implications for national and local politics alike. John Wagner,, "Government lawyers step up effort to get a citizenship question on 2020 Census, court filing shows," 5 July 2019 Still, anyone who’s seen any of the show’s previous 13 seasons realizes giving intimate access to the crew is the crux of the show, especially on cutdown day when a rookie’s dream of making it to the NFL doesn’t come true. Jon Becker, The Mercury News, "Raiders wary of giving ‘Hard Knocks’ too much access," 27 July 2019 Community projects like this Minecraft mission are the crux of the new-age relationships formed between streamers and their audiences. Cian Maher, The Verge, "The streamer who built a giant Starbucks island in Minecraft," 15 July 2019 Medical examiners concluded White was probably strangled with a sheet, towel or ‘‘crux of the elbow.’’ The officer who moved his body pleaded guilty to obstruction. Aaron C. Davis,, "Autopsy finds broken bones in Jeffrey Epstein’s neck, deepening questions around his death," 15 Aug. 2019 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

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

11 Sep 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).


miscellaneous remnants or debris

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