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

This is a nation in which military service is near universal for both sexes and a state of war has been continuous for 2½ years.

From The Wall Street Journal • Apr. 7, 2026

The assembly is expected to swiftly elect the next supreme leader, especially with Iran being in a state of war.

From Salon • Mar. 6, 2026

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

“A state of war is not a blank check for the President,” said Justice Sandra Day O’Connor in 2004.

From Los Angeles Times • Mar. 28, 2025

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