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casus belli

casus belli

2 9.9
An event used to give a reason to start a war
  • noun
  • /ˈkeɪsəs ˈbɛlaɪ/
  • Literature
translation icon : casus belli
  • The government cited the attack as a casus belli for declaring war.
  • providing a casus belli

Examples

  • More forcefully than ever, politicians and analysts assert that the next casus belli in the Middle East will be control and use of water.

    Academic text (1993)
  • The reason is that for one party to insist on all the water would in fact be a casus belli; and to risk a war to simply increase one's access to water is economically foolhardy.

    Academic text (2002)
  • Because of his extreme importance within the organization, and particularly its military wing, his death is casus belli: cause for war.

    Blog text (2)
  • Israel called this a casus belli, and international efforts to resolve the dispute were undertaken.

    Academic text (2006)
  • Would that suffice as a casus belli against a nuclear Iran as far as the Obama administration was concerned?

    Academic text (2010)
  • If someone was looking for a casus belli, Saddam Hussein provided it on 2 August.

    Academic text (1991)
  • As water scarcity appears to grow, there are repeated predictions that water will become a major casus belli all over the globe.

    Academic text (2006)
  • We shall obtain an American guarantee of free passage through the Straits of Tiran, our main casus belli.

    Fiction book (1993)
  • For example, in the wake of the Suez War in 1956, Israel insisted on freedom of navigation in the Red Sea since its blockade by Nasser had been a casus belli for the war.

    Academic text (2010)
  • In using the phrase "just cause," Norton referenced a well-known formula from the European laws of war requiring that nations possess a valid casus belli, or cause of war, before engaging in hostilities.

    Academic text (2016)

How Provocative

aggression
  • Formal
128 4.4
casus belli
  • Literature
2 9.9
provocation
58 7.2
incident
2.7

Surface Forms

casus belli singular
casus belli plural

Morphology

casus + belli

The phrase literally combines Latin casus (case, occasion, cause) + belli (genitive of bellum, ‘of war’) to mean a ‘case or cause of war’, so its meaning is compositionally derivable if a learner knows both constituents and recognizes the genitive relationship. However, because the constituents are Latin forms (and ‘belli’ may not be recognized as ‘of war’ by learners without Latin knowledge), the compositionality is not fully transparent to an average B1 learner, making it only partially predictable.

Etymology

Casus belli is a Latin phrase from the words casus (meaning 'case' or 'cause') and belli ('of war'). It paints the image of a clear reason used to start a war, so today it means an event leaders use to 'justify' going to war.