Boris is a tiny lunar crater on the Mare Imbrium, to the northeast of the crater Delisle. It lies near the southwest extremity of a sinuous rille that is designated Rima Delisle. This rille meanders to the northeast, towards the crater Heis, before vanishing into the lunar mare. (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.