declaration of war

 

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declaration of war

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declaration of war (plural declarations of war)

1. A formal announcement by a country or other body with military capability that it is in a state of war with another such entity.
   • 2022 January 12, Dr. Joseph Brennan, “Castles: ruined and redeemed by rail”, in RAIL, number 948, page 55:

     Make no mistake, the sway of the railways' mandate in the middle of the 19th century was, in some quarters, a declaration of war on the old.

• act of war