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 figurativelyThe state has declared war on illiteracy.
Cite this Entry
“Declare war.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/declare%20war. Accessed 11 Mar. 2026.
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