Debye is a lunar crater that is located in the northern hemisphere , as seen from the Earth. It lies to the south of the crater Chappell, to the southwest of the walled plain Rowland, and to the east of D'Alembert. The outer rim of this crater has been heavily battered by impacts, and is somewhat distorted from the form of a circle. The northeast rim in particular has become straightened by impact modification, and the crater rim as a whole has a roughly polygonal shape. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.