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Synonyms

crux

1 American  
[kruhks] / krʌks /

noun

plural

cruxes, cruces
  1. a vital, basic, decisive, or pivotal point.

    The crux of the trial was his whereabouts at the time of the murder.

    Synonyms:
    gist, core, heart, essence
  2. a cross.

  3. something that torments by its puzzling nature; a perplexing difficulty.


Crux 2 American  
[kruhks] / krʌks /

noun

Astronomy.

genitive

Crucis
  1. Southern Cross.


crux 1 British  
/ krʌks /

noun

  1. a vital or decisive stage, point, etc (often in the phrase the crux of the matter )

  2. a baffling problem or difficulty

  3. mountaineering the most difficult and often decisive part of a climb or pitch

  4. a rare word for cross

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Crux 2 British  
/ krʌks /

noun

  1. the more formal name for the Southern Cross

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of crux1

1635–45; < Latin: stake, scaffold, or cross used in executions, torment; figurative senses perhaps < New Latin crux ( interpretum ) (commentators') torment, a difficult passage in a text; crucial

Origin of Crux2

< Latin: a cross

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The crux of the dispute is what it means for a child to be subject to U.S. “jurisdiction.”

From The Wall Street Journal

The crux of his argument is better-than-anticipated industry pricing in the first quarter, which “has seemingly moved well ahead of expectations set previously by Micron.”

From Barron's

What will become of this nursery in the wild in the next hundred years, or thousand, is the crux of a scientific and policy dispute.

From Los Angeles Times

But Iran’s nuclear program, in particular its enrichment of uranium, is at the crux of the negotiations.

From The Wall Street Journal

At the crux of the case was whether Rogers knowingly attempted to advance China’s interests or was unwittingly duped into providing information to spies he thought were academics.

From The Wall Street Journal