Buffon is a lunar crater on the southern hemisphere on the far side. It lies a crater diameter south of the large walled plain Chebyshev. To the northeast is the crater Langmuir and to the southwest is Leavitt. Buffon lies nearly at the midpoint between these formations. (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.