Spurr is the lava-flooded remains of a lunar impact crater. It is located in the midst of the Palus Putredinis plain, to the southeast of the crater Archimedes. Only the southern half of the rim protrudes significantly through the lunar mare material, while the northern section of the wall has a resemblance to a ghost crater rim. (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.