Komarov is a lunar crater that lies across the southeastern edge of Mare Moscoviense, on the northern hemisphere of the far side. It is a complex feature with an irregular appearance. The northern rim bulges outwards into the mare, giving the crater a pear shape. The regions around the northeastern and southern rims are rugged and uneven, and the crater floor in between has been resurfaced by lava flows that have completely submerged the western third of the interior. (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.