Cleaning the pipes

Anglo-American slang term used to describe the act of mastubation in order to empty one's testicles of a thick, fat, juicy load of baby-batter in order to start a newer batch.
Or, in the case of the film 'There's Something About Mary,' the theory that "cleaning your pipes" will steady your nerves before a date because your body will not think you are trying to have sex because you will have tricked it into thinking you have done already...

To jerk off, especially prior to a date, so you aren't thinking about sex all the time.

masturbation to prevent the pipes from clogging, which can lead to the back up of sperm that flows directly to the brain causing awkward sexual advances, undue violence, and masturbation in creative and sometimes inappropriate places.

When you go into the bathroom and you end up taking a shit, pissing, and ending with a good ol' hearty fap.

Urination by a man following an act of masturbation or sex. Presumably any semen left in the tip of the penis will be cleaned out by the pressurized urine stream.

1. To clean a pipe in a stroking motion, in a way in which it looks like masturbating.

2. To be jerked off

Tugging your meat until you ejaculate, and then pissing. This supposedly cleans your urethra (hence, Cleaning the Pipes)

It stings, and that's evidence that it's doing what its name says.

It can also be done right before having sexual intercourse, so you don't get a woman pregnant, and you don't have to wear a condom.