Belligerent

In international law. A term used to designate either of two nations which are actually in a state of war with each other, as well as their allies actively co-operating; as distinguished from a nation which takes no part in the war and maintains a strict indifference as between the contending parties, called a "neutral."

U. S. v. The Ambrose Light (D. C.) 25 Fed. 412; Johnson v. Jones, 44 III. 151, 92 Am. Dec. 159.