Someone who excites their own sexual organs for fun, usually until reaching orgasm. Calling someone a masturbator carries the insinuation that they are unable to find a willing sexual partner and must therefore resort to doing it themselves. Billy Connolly, the Scottish comedian, has a a funny sketch where he describes his first sexual experience: “It was dark, it was hurried. I was alone!”.
“Stop being a masturbator and come and join the party!”.