Bohr is a lunar crater that is located near the western lunar limb, in the area that is affected by librations. It is attached to the southwestern rim of the larger, eroded Vasco da Gama formation, and to the southeast of the crater Einstein. The rim is worn and eroded, and a pair of small, bowl-shaped craters lies across the western rim. The rim to the northeast has been shored up by the adjacent Vasco da Gama, but the remainder forms an irregular ring of rugged ground. (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.