Lovell is a small lunar crater that lies across the eastern edge of the walled plain Apollo, on the far side. The rim is sharp-edged, with some slight wear along the northwestern bend. The featureless inner walls slope directly down to the uneven interior floor. (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.