\ˈkrəks, ˈkru̇ks \
plural cruxes also cruces\ ˈkrü-​ˌsēz \

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

At the crux of the Cass-Henry debates are two issues: preservation — the goal of maintaining historical integrity in a rapidly changing neighborhood; and affordability, to stop displacement. Allie Gross, Detroit Free Press, "Cass-Henry Historic District vote delayed, leaving Ilitch buildings in limbo," 3 July 2018 But money could still be at the crux of the problem for TCU. Stefan Stevenson, star-telegram, "Why money, if not salary, could be TCU's problem when it comes to keeping Schlossnagle," 29 May 2018 For Chung, uncovering the nuances between human and robot interaction is at the crux of the residency. Elizabeth Stinson, WIRED, "What Artists Can Teach Us About Making Technology More Human," 10 May 2018 Get our daily newsletter At the crux of this drama are not only entertainment-industry egos—always outsized—but also divergent priorities. The Economist, "Viacom rejects a merger with CBS," 5 Apr. 2018 Because she, in fact, designed the advertising model that is sort of at the crux of this issue. Fox News, "President Trump to sign proclamation sending National Guard troops to the border," 5 Apr. 2018 While the novel is essentially Hero’s, the question as to what extent any of its characters are truly able to feel at ease in their own lives (and in their own skins) is at the crux of the matter. Megan O'grady, Vogue, "America Is Not the Heart," 3 Apr. 2018 Local food and energy are at the crux of this vision. Hannah Seligson, Town & Country, "Larry Ellison Wants Lanai to Be the Most Incredible Resort in the World," 7 Apr. 2017 But whether denuclearization on the Korean Peninsula means the same thing to Mr. Trump and Mr. Kim goes to the crux of their meeting and could ultimately shape its success or failure. Rick Gladstone, New York Times, "Trump and Kim May Define ‘Korea Denuclearization’ Quite Differently," 10 June 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

6 Nov 2018

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Time Traveler for crux

The first known use of crux was in 1718

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playful or foolish behavior

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