When a inmate put his sheets around the bottom bunk to make a shack to Jack off in
Go away I'm going to make a Jack shack
by Johnny Ex con March 26, 2018
Get the Jack shack mug.
When your wife/girlfriend is menstruating (i.e. on the rag) and the only sexual release available to you is masturbation.

(This is a tribute to the late comedian Robert Schimmel, who coined this phrase before his death in a song of the same name.)
John: "Hey. You alright, man? you look tense."

Ray: "Yeah. The wife is on the rag, man.. Gonna be a long week in the Jack Shack."

John: "Ah. Gotcha."
by Averant September 19, 2010
Get the Jack Shack mug.
the stall in a dorm or shared bathroom that you or someone else always beats their meet in.
"Has anyone seen Dan?"
"He's in the bathroom and I saw him go into the jack off shack so it'll be a while"
by lillukey August 17, 2018
Get the Jack off shack mug.