elongated protrusion of a geopolitical entity

A panhandle is a word used in geography. What people mean when they talk about panhandles is a narrow strip of land, that is surrounded on all sides except one, by one or more countries or regions. The strip of land is connected to the country or region it belongs to on one side only. This looks like the handle of a frying pan.

Map of the U.S. state of Oklahoma, with its panhandle marked in red

Panhandles include: