state of war

American  

noun

1. a condition marked by armed conflict between or among states, existing whether or not war has been declared formally by any of the belligerents.

2. a legal condition initiated and concluded by formal declaration, and not necessarily involving armed conflict.

3. the duration of such a condition.

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state of war British  

noun

1. a period of armed conflict between states, regardless of whether or not war has been officially declared

2. a legal condition begun by a declaration of war and ended formally, during which the rules of international law applicable to warfare may be invoked

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Etymology

Origin of state of war

First recorded in 1945–50

Example Sentences

Lebanon and Israel are still technically in a state of war, but all the recent armed conflicts with Israel were fought by Hezbollah, not the Lebanese military.

From Barron's • Nov. 8, 2025

With large parts of Myanmar under opposition control and in a state of war, holding this election is a formidable logistical exercise for the country's military rulers.

From BBC • Aug. 18, 2025

Or leaders, when you look at Hamas, who calculate that an endless state of war serves their interests.

From Salon • Mar. 13, 2024

“A state of war is not a blank check for the president,” she declared.

From Los Angeles Times • Dec. 1, 2023

He pulled a paper from his pocket and handed Sazonov a declaration stating that because of Russia’s continued mobilization, a state of war now existed between Russia and Germany.

From "The War to End All Wars: World War I" by Russell Freedman