Pilâtre is a lunar crater near the southwestern limb. It is located just to the north-northwest of the much larger walled plain Hausen. The satellite crater Pingré S is attached to the eastern rim, with Pingré itself located farther to the northeast. Just to the west-southwest is Chappe, a formation of similar dimension to Pilâtre. (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.