Franciszek; Polish astronomer (1789-1848). (Spelling changed from Armínski.)
Armiński is a small lunar impact crater on the far side , to the northeast of the large walled basin Gagarin. To the northwest is the crater Beijerinck, and to the southeast lies Cyrano. The rim is slightly oval in shape, being somewhat elongated in the northeastern direction. It forms a double-crater with Armiński K, a slightly smaller formation nearly attached to the southeast rim. (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.