Laying in bed, chubbed up, waiting for your roommate to go to sleep so you can pleasure yourself
"I had a Louisville Slugger-sized hardon last night and needed to crank one out, but my roomie was awake, watching some dumbass videos. I was up masturwaiting until 1:30am!"
The timespent wait for porn to buffer. The time that one spends waiting until the selected material is buffered and ready for viewing; at which point one can proceed with pleasuring one self.
I got home and due to my slow connection speed I had to masterwaiting until I could watch my girlAva Addams and finish myself enjoyment.
Waiting for everyone in your house to go to sleep to spare having to hear them or them hear you while masturbating.
John: Why the hell are you so tired?
Bill: My brother wouldn't go to sleep, I was masturwaiting until like 2AM for fucks sake.
John: What the fuck is masturwaiting?
Bill: Check urban dictionary fag.