look up any word, like tribbing:
 
1.
For one to nut in a girls mouth.
I gave michelle a protein shake for breakfast..
by war-su-gi January 24, 2003
 
2.
A sexual act in which one person shoots jizz (a protein shot) into the other's mouth and then shake their head vigorously.
Gwen: "Let's get out of here and grab a beer."
Richard: "Are you insane? You know my midterm and finals ritual. I study til 11, 9 solid hours of sleep, protein shake in the morning."
(from 'Van Wilder')
by Nick D February 26, 2004
 
3.
a silly metaphor for semen
"Last night Amber swallowed a big cup of my protein shake. She said it was deeeeee-liscious!"
by B.Diddy August 02, 2007
 
4.
In the world of strength-athleticism, supplements for growth are often used. Protein shakes are powedered substances which are mixed with milk, oragange juice etc. to produce a drink apporoximately 70% protein.

consumed after exercise, the protein rebuilds the muscle bigger and stronger.
MMMMMM, banana flavour!
by Kung-Fu Jesus April 17, 2004
 
5.
-Yo, she really took your protein shake?
-Hell yeah! She swallowed like a pro!
by ripR1 August 16, 2008
 
6.
The Sexual process of masturbating a male and catching the semen in your mouth.
Hooker: I like to keep myself healthy by enjoying a protein shake right after a heavy workout session.
by Jared Ellis March 09, 2008
 
7.
Slang for male ejaulate (semen), especially as a result of oral sex.

This term probably came into being upon the meeting of bodybuilder culture and its emphasis on whey- and other protein-based powders (dissolved in liquid resluting in a flavored milkshake-like drink), with contemporary gay culture.
Todd, come to my house after school. We'll hole up in my room and do some heavy lifting, hopefully ending in a protein shake or two winks.
by al-in-chgo August 19, 2010