declare war

phrase

: to officially decide to fight or go to war
Congress has the power to declare war on/against other countries.
—often used figuratively
The state has declared war on illiteracy.

Examples of declare war in a Sentence

Recent Examples on the Web
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While the Constitution says only Congress can declare war, the president as commander-in-chief is also able to engage the military. — Lisa Mascaro, Chicago Tribune, 24 Sep. 2026 While Congress has the authority to declare war, the president as the commander-in-chief executes it. — ABC News, 9 Sep. 2026 As of now, the president’s decision to declare war on Iran appears to be a catastrophic mistake rather than an act of bravery. — Voice Of The People, New York Daily News, 25 July 2026 One camp sticks strictly to the claim that Congress alone has the power to declare war. — Literary Hub, 1 July 2026 See All Example Sentences for declare war

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Cite this Entry

“Declare war.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/declare%20war. Accessed 3 Oct. 2026.

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