Slapping the monkey 

British slang for masturbation

John- *fap fap fap*
Bill- hey... what are you doing
John- Not slapping the monkey if thats what you think

Slapping the monkey by Shamingo June 18, 2011

Slapping the monkey 

It is a procedure that involves whacking ones genitals for pleasure and for escaping the boredom of routine life.

Viren Naidu believes in slapping the monkey after a hard days night before he retires for the day.

Slapping the monkey by Kunal Guha September 22, 2005

swapping the monkey 

a feat of stealth used by thieves to successfully pilfer items atop a pressure plate.

wife speaking to her husband: why is this coffee so weak, were you fucking swapping the monkey with your cup in the coffee maker again? that's it! we're getting a divorce!

swapping the monkey by WordRepoMan January 15, 2013