war. 1. Hostile conflict by means of armed forces, carried on between nations, states, or rulers, or sometimes between parties within the same nation or state; a period of such conflict <the Gulf War>. • A state of war may also exist without armed conflict; for example, the treaty formally ending the World War II state of war between the United States and Japan was signed seven years after the fighting ended in 1945. [Cases: War and National Emergency  1. C.J.S. War and National Defense §§ 1, 5.]

civil war.An internal armed conflict between people of the same nation; esp. (usu. cap.), the war from 1861 to 1865, resulting from the Confederate states’ attempted secession from the Union.

imperfect war.A war limited in terms of places, persons, and things. mixed war.A war between a nation and private individuals. perfect war.A war involving an entire nation against another. private war.A war between private persons. public war.A war between two nations under authority of their respective governments.

solemn war.A war formally declared — esp. by public declaration — by one country against another.

2. A dispute or competition between adversaries <fare wars are common in the airline industry>.3. A struggle to solve a pervasive problem <America’s war against drugs>.
[Blacks Law 8th]