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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 play \ˈkä-ˌsüs-, ˈkā-ˌsüs-\
: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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