oblitérer

Oblitérer is a French verb meaning to obliterate, erase, or render something unusable or illegible. In everyday language it can refer to erasing writing, sealing or covering something, or destroying a seal or mark. In postal history and philately, oblitérer has a specialized meaning: to cancel a postage stamp so that it cannot be reused.

The cancellation, or oblitération, is usually a postmark or other imprint applied by a postal authority. Its purpose is twofold: to show that the stamp has already served its postage and to prevent unauthorized reuse. The appearance of oblitérations varies widely by country and period. Some are simple pen or pencil cancellations; others are mechanical or hand-stamped devices that produce circular or oval date stamps, bars, or wavy lines. The French term cachet d'oblitération refers to the cancellation impression itself. In philatelic practice, the type, clarity, date, and location indicated by the oblitération contribute to a stamp's postal history and can affect collectibility and value.

Etymology: oblitérer comes from Latin oblitterāre, to erase, via Old French and Middle French.

In other contexts, oblitérer can mean to destroy or hide official content on a document, for example by stamping or erasing parts of a seal or inscription to prevent reuse or alteration.