moonlet

[moon-lit]

noun

a small natural or artificial satellite, as one of a number of natural satellites thought to be embedded in the ring system of Saturn.

Origin of moonlet

First recorded in 1825–35; moon + -let

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

The Arrow, the Hound and the Lady circled the moonlet, swinging inward to the attack.
The Peacemaker
Alfred Coppel