Combat zone and Theater of war

Combat zone noun - A military area where combat forces operate.

Theater of war and combat zone are semantically related In some cases you can use "Theater of war" instead a noun phrase "Combat zone".

Theater of war noun - The entire land, sea, and air area that may become or is directly involved in war operations.

Combat zone and theater of war are semantically related in location of military fights topic. You can use "Combat zone" instead a noun phrase "Theater of war", if it concerns topics such as place of warring.