Coup

A sudden, violent, and illegal seizure of power from a government, typically carried out by a small group within the existing state apparatus. Coups often involve military forces overthrowing civilian leadership or rival military factions seizing control.

Short for French 'coup d'état' meaning 'stroke of state,' first used in this political sense in the 1640s. The term emphasizes the sudden, decisive nature of the power seizure, like a swift blow or strike against the existing order.