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casus belli

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noun ca·sus bel·li \ˈkä-səs-ˈbe-ˌlē, ˈkā-səs-ˈbe-ˌlī\

Definition of casus belli

plural

casus belli

\ˈkä-ˌsüs-, ˈkā-ˌsüs-\

  1. :  an event or action that justifies or allegedly justifies a war or conflict

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Origin and Etymology of casus belli

New Latin, occasion of war

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