Dechen is a small, bowl-shaped crater that is located in the northwest part of the Oceanus Procellarum, near the northwest limb. The rim of the crater projects slightly above the surrounding lunar mare, and the interior is symmetrical and nearly featureless. It lies to the northeast of the crater Harding, but is otherwise isolated. (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.