A moon circle is the end result of someone standing in the road and pissing while rotating. This creates a circle of piss that is reflected by the moon or the headlights of a car. Moon circles are usually best seen on an asphalted road. While mostly seen on rural roads they have also been sighted on urban roads as well.
Did you see that moon circle in the middle of the road last night?
by Jay Dubbee June 01, 2011