moon

The moon is the shining white and grey object in the sky at night. It appears to change shape from round (a full moon) to a crescent and back again. It's like a small planet that goes around the Earth.

Example: I was able to see the road because there was a full moon that night.

A moon is a thing like a small planet that goes around another planet.

Example: Galileo saw four moons of Jupiter: Callisto, Europa, Ganymede and Io.

If you moon someone, you show them your bare buttocks.

Example: Someone in the car pulled down their pants and mooned us as they drove past.