Named after Rafael Bombelli - Italian mathematician (1526-1572).
Bombelli is a small lunar impact crater that is located in the highlands to the north of the Sinus Successus. It was previously designated Apollonius T before being named by the IAU. The crater Apollonius is located to the east-southeast. This is a roughly circular crater with a slight outward protrusion to the south-southwest. (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.