Rooting from YouTuber Jenna Marble's video, Jenna's Drunk Art School: Balloon Art, It is basically gripping the dick as hard as you can until it isn't hard anymore.
Girl 1: Did you and John finally do it last night?
Girl 2: No....
Girl 1: Did you gorilla grip the dick again?
Girl 2: ........maybe
Girl 2: No....
Girl 1: Did you gorilla grip the dick again?
Girl 2: ........maybe
by This Dick Though January 20, 2015
 Get the Gorilla Grip the Dickmug.
Get the Gorilla Grip the Dickmug. “I can’t think of anybody who had more impact than Dr. Dobson,” on rousing evangelicals to the polls, Richard Viguerie, a GOP direct-mail guru, recently told U.S. News & World Report. “He was the 800-pound gorilla.”
by The Wu Factor November 16, 2005
 Get the 800-pound gorillamug.
Get the 800-pound gorillamug. a member of the male species
by *** November 17, 2003
 Get the half witted gorillamug.
Get the half witted gorillamug. Basically is when you expload on a womans back side (Cum on her back) you rub it on her back then put it in her face.
by Spanky57 August 17, 2006
 Get the Sliver Back Gorillamug.
Get the Sliver Back Gorillamug. by Anonymous March 13, 2003
 Get the Silver Backed Gorillamug.
Get the Silver Backed Gorillamug. by chernobylspice December 11, 2003
 Get the Gorilla in the washing machine.mug.
Get the Gorilla in the washing machine.mug. the act of two or more ape-like animals activly rubbing against eachother in a sexual motion, but often used in the context with crazy human sex
by barch September 24, 2005
 Get the humping like gorillasmug.
Get the humping like gorillasmug.