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
In the run-up to the Iraq War, diplomacy and weapons inspections became a means to an end: building a casus belli.
—
Foreign Affairs, 18 Oct. 2012
State media claimed without providing any evidence that the hospital was being used as a base for the Azov Battalion, a small far-right nationalist group often used as casus belli by Putin for false claims that the Ukrainian government is rife with Nazis.
—Michael Biesecker, Erika Kinetz, Beatrice Dupuy, Anchorage Daily News, 26 Mar. 2022
In each instance, the casus belli is complicated stuff.
—Anthony Lane, The New Yorker, 14 Oct. 2022
Critical voices challenging Putin’s casus belli and highlighting Russia’s isolation, the atrocities committed daily by Russian troops and the disastrous costs of the conflict for Russia have been all but silenced.
—Daniel Beer, Washington Post, 29 Sep. 2022
Less can be said of the muddled casus belli, as Dahomey’s struggle for independence unpersuasively evolves into a proto-pan-African struggle for abolition.
—Julian Lucas, The New Yorker, 16 Sep. 2022
By exposing this plan, the Biden administration sought to undermine its emotional power and stop the Kremlin from manufacturing a casus belli, or justification for war.
—Scott Radnitz, The Conversation, 17 Feb. 2022
India was itching to intervene militarily but lacked a cast-iron casus belli.
—Tunku Varadarajan, WSJ, 18 Mar. 2022
The Tonkin Gulf incident, which provided a casus belli for the Vietnam War, gets a single sentence.
—Fred O’Brien, National Review, 3 Mar. 2022
See More
Foreign Affairs, 18 Oct. 2012
State media claimed without providing any evidence that the hospital was being used as a base for the Azov Battalion, a small far-right nationalist group often used as casus belli by Putin for false claims that the Ukrainian government is rife with Nazis.
—Michael Biesecker, Erika Kinetz, Beatrice Dupuy, Anchorage Daily News, 26 Mar. 2022
In each instance, the casus belli is complicated stuff.
—Anthony Lane, The New Yorker, 14 Oct. 2022
Critical voices challenging Putin’s casus belli and highlighting Russia’s isolation, the atrocities committed daily by Russian troops and the disastrous costs of the conflict for Russia have been all but silenced.
—Daniel Beer, Washington Post, 29 Sep. 2022
Less can be said of the muddled casus belli, as Dahomey’s struggle for independence unpersuasively evolves into a proto-pan-African struggle for abolition.
—Julian Lucas, The New Yorker, 16 Sep. 2022
By exposing this plan, the Biden administration sought to undermine its emotional power and stop the Kremlin from manufacturing a casus belli, or justification for war.
—Scott Radnitz, The Conversation, 17 Feb. 2022
India was itching to intervene militarily but lacked a cast-iron casus belli.
—Tunku Varadarajan, WSJ, 18 Mar. 2022
The Tonkin Gulf incident, which provided a casus belli for the Vietnam War, gets a single sentence.
—Fred O’Brien, National Review, 3 Mar. 2022
See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'casus belli.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
Etymology
New Latin, occasion of war
First Known Use
circa 1841, in the meaning defined above
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Dictionary Entries Near casus belli
Cite this Entry
“Casus belli.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/casus%20belli. Accessed 2 Dec. 2023.
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