Masterbassion 

(n.);masterbassing-(v.) pronounced: Mast-er-bash-un
The stimulation of ones own bass guitar, especially slapping, which results in immediate pleasure and self-gratification. Depending on the length and intensity of masterbassion, pain and/or blisters may develop.

Idle hands lead to masterbassion.

Masterbassion by Glason j Laausser March 26, 2010

Masterbathon 

a masterbathon is a day that you stay home from school "sick" so you can beat off so many times that you are dry and chaffed and can't walk so the next day you have to stay home and do it all over again

Mike: "Damn jimmy has been out of school all week"
Steve: "I konw he must be having a masterbathon"

Masterbathon by LifeguardSteve April 27, 2004

masturbathing 

The act of jacking off while in the shower.

Why were you taking so long in the shower?

Oh, I just got done masturbathing.

masturbathing by cabbage206 August 15, 2009

masterbacin' 

what you do when looking at bacon porn.

Last night, when I was looking at bacon porn, I started masterbacin'

masterbacin' by cjsnickers April 23, 2009

masterbassing 

The act of self pleasure while listening to dubstep or any other bass heavy music.

Toby: Did you see Danny at that Excision concert last night?
Luke: Yeah man, he was totally masterbassing all over the place.
Toby: And when that bass dropped?
Luke: Yeah...I'm pretty sure Danny had to change his pants afterward.

masterbassing by whitepeoplelikedubsteptoo! February 20, 2011

masterbating with a cheese grater 

Doing a task that is not a good idea

Moving this piano without help is like masterbating with a cheese grater.

masterbating with a cheese grater by matt1975 September 10, 2012

Masturbasting 

(V.) -ed The act of masturbation on or over somebody else's food ,evenly coating the object in one's own semen and/or vaginal fluid.

John was masturbasting his, soon to be ex-girlfriend's turkey, cause the bitch had it coming.

Masturbasting by Martin the Spartan March 19, 2010