casus belli
noun
ca·sus bel·li
ˈkä-səs-ˈbe-ˌlē 
ˈkā-səs-ˈbe-ˌlī
ˈkā-səs-ˈbe-ˌlī
plural casus belli
: an event or action that justifies or allegedly justifies a war or conflict
Examples of casus belli in a Sentence
Recent Examples on the Web
That is the nature of this latest Israeli casus belli too.
—
Melik Kaylan, Forbes.com, 16 June 2025
But what Putin can live with today may become a casus belli tomorrow.
—George Beebe, TIME, 1 July 2024
Baghdad also awkwardly cited the PKK’s presence in Kirkuk as casus belli for conflict, securing Ankara’s support for the operation.
—Behnam Ben Taleblu, Foreign Affairs, 8 Nov. 2017
Debate over this proposal has so far been scant and ignored the casus belli.
—Christian Schneider, National Review, 21 Dec. 2023
See All Example Sentences for casus belli
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Melik Kaylan, Forbes.com, 16 June 2025
But what Putin can live with today may become a casus belli tomorrow.
—George Beebe, TIME, 1 July 2024
Baghdad also awkwardly cited the PKK’s presence in Kirkuk as casus belli for conflict, securing Ankara’s support for the operation.
—Behnam Ben Taleblu, Foreign Affairs, 8 Nov. 2017
Debate over this proposal has so far been scant and ignored the casus belli.
—Christian Schneider, National Review, 21 Dec. 2023
See All Example Sentences for casus belli
Cite this Entry
“Casus belli.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/casus%20belli. Accessed 13 Jul. 2025.
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