- a condition marked by armed conflict between or among states, existing whether or not war has been declared formally by any of the belligerents.
- a legal condition initiated and concluded by formal declaration, and not necessarily involving armed conflict.
- the duration of such a condition.
- a period of armed conflict between states, regardless of whether or not war has been officially declared
- 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
