Engaging in extremely an extremely unproductive activity (a la doing nothing and having ur balls in ur hands) while you could be actively doing something that would benefit you or other people around you.

When A Guy Holds His Dick And Rubs His Hand Up And Down Getting Faster Until It Feels Good And He Sperms.

Something preeteen boys do to feel the sensation of some real sex

when someone playz with themself for guyz rubbing there hand up and down their cock a gurl might finger her self

To move your hand up and down your shaft or in and out your vigina (see masturbate)

when a male cannot find a girl to have sex with so he is forced to pleasure himself.

To releive one's thelf in thexual enlightenment by rubbing the head, or pinching the cliterus over and over and over and over.