Petit is a small, bowl-shaped lunar impact crater that is located on the northwestern edge of the Mare Spumans.

The crater has a prominent ray system.

The name is appropriate, since petite means small in French.

But it was actually named in honor of Alexis Thérèse Petit, a French physicist.

Petit was previously designated Apollonius W before being given a name by the IAU in 1976.