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casus belli

[key-suh s bel-ahy, bel-ee; Latin kah-soo s bel-lee] /ˈkeɪ səs ˈbɛl aɪ, ˈbɛl i; Latin ˈkɑ sʊs ˈbɛl li/
noun, plural casus belli
[key-suh s bel-ahy, bel-ee; Latin kah-soos bel-lee] /ˈkeɪ səs ˈbɛl aɪ, ˈbɛl i; Latin ˈkɑ sus ˈbɛl li/ (Show IPA)
an event or political occurrence that brings about a declaration of war.
Origin of casus belli
1840-50; < New Latin: literally, occurrence of war Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for casus belli
Historical Examples
  • He would be an "Ishmaelite," finding "casus belli" in all the purposes of fate.

    Oswald Langdon Carson Jay Lee
  • He adds that with the Germans war is instinctive; there is no casus belli at all.

    The Psychology of Nations G.E. Partridge
  • The Markgrafs casus belli was now gone; but his demands knew no bounds.

    The Story of Nuremberg Cecil Headlam
  • The farmer had taken his cats part, and scolded the man, and hence the casus belli.

    Cats W. Gordon Stables
  • If not, although a man of peace, I shall consider it a casus belli!

  • The casus belli was simple, but, as reported, most irritating.

    Scotch Wit and Humor

    W. H. (Walter Henry) Howe
  • If the Count Ferroll is discomfited by the prince, it may be a casus belli.

    Endymion Benjamin Disraeli
  • It was evident that no casus belli existed in any international sense.

    Under Four Administrations Oscar S. Straus
  • His casus belli, accurately worded, would have read curiously.

  • It is the right of a sovereign State and by no code of ethics a casus belli.

    The Evidence in the Case James M. Beck
British Dictionary definitions for casus belli

casus belli

/ˈkɑːsʊs ˈbɛliː/
noun (pl) casus belli (ˈkɑːsʊs ˈbɛliː)
an event or act used to justify a war
the immediate cause of a quarrel
Word Origin
literally: occasion of war
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
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Word Origin and History for casus belli

1849, from Latin casus "case" (see case (n.1)) + belli, genitive of bellum "war" (see bellicose). An act justifying war.

Online Etymology Dictionary, © 2010 Douglas Harper
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