Commissary

A commissary is someone delegated by a superior to execute a duty or an office; in a formal, legal context, one who has received power from a legitimate superior authority to pass judgment in a certain cause or to take information concerning it.

Word history
The word is recorded in English since 1362, for "one to whom special duty is entrusted by a higher power". This Anglo-French word derives from Medieval Latin commissarius, from Latin commissus (pp. of committere) "entrusted,".

Other uses
In the United States armed forces and prisons, as well as the United Nations, it has the derived meaning of a store for provisions, with the original military meaning referring to an officer or official responsible for food, stores, or transport for a body of soldiers. The United States Defense Commissary Agency operates commissaries that are similar to supermarkets, providing service members with most of the same available in the U.S. economy regardless of where they are stationed worldwide. Commissaries sell primarily grocery articles; other items can be purchased at a base exchange/post exchange.

In the US film industry, the word commissary is often used to mean dining room.

Sources and references

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 * EtymologyOnLine