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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.

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

There’s no glossary, but the main terms are clear enough: to “send” a climb is to finish it; a “crux” is a crucial pivot point.

From Los Angeles Times

The crux of the issue is that she paid for work on a trust-owned asset before she legally owned it, which is not the same thing as a buyer upgrading their own home.

From MarketWatch

At the crux of the issue is the legality of slot-machine-type terminals.

From Los Angeles Times

And this is the crux of the matter.

From BBC