A government-issued stamp that can be used in exchange for food WordNet 3.0 & Open English WordNet

A ration stamp, ration coupon, or ration card is a stamp or card issued by a government to allow the holder to obtain food or other commodities that are in short supply during wartime or in other emergency situations when rationing is in force. Wikipedia

Indicating the right to rationed goods Wikipedia Disambiguation

A stamp or similar paper document (e.g. coupon) issued to be exchanged in shops or storage facilities for food, or (by extension) for other essential provisions, notably in a rationing system or as a non-financial form of welfare benefit. Wiktionary

Stamp or similar issued to be exchanged for food, or other essential provisions. Wiktionary (translation)

A food stamp. Wiktionary