1) Former field food 2) Old military fare 3) Platoon provender 4) Three-course WWII offering 
The K-ration was an individual daily combat food ration which was introduced by the United States Army during World War II. It was originally intended as an individually packaged daily ration for issue to airborne troops, tank corps, motorcycle couriers, and other mobile forces for short durations. The K-ration provided three separately boxed meal...
[n] - a small package of emergency rations
noun a small package of emergency rations; issued to United States troops in World War II
an emergency field ration for U.S. armed forces when other food or rations are not available, consisting of three separate packaged meals of concentrated or dehydrated food. Cf. C ration.