Named after Gyula Fényi - Hungarian astronomer (1845-1927).
Fényi is a small lunar crater on the far side. It lies near the southern edge of the huge, braided skirt of ejecta that surrounds the Orientale impact Basin to the north. Less than two crater diameters to the southwest is the much larger crater Mendel. Much of the rim and nearly all of this crater have been buried under material from the Orientale Basin impact. (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.