shower jaw 

similar to curb stomping but done in prison showers where the victim bites the shower head and you high kick his head into the shower head, thus giving him a shower jaw,

dave:wtf happened to you?
joe:i jus gawt shower jaw
dave;that sucks
joe:fukk yu ash howl

shower jaw by james maddrox June 22, 2008

showerjack 

v. when, in a college dormitory bathroom or other communal restroom facility, all of the shower stalls are occupied, and an individual who is short on time (or manners) strips off his clothes and runs into a random stall, gleefully yelling, "showerjack!" and forcing the former occupant out.

n. an instance of the above maneuver.

1) "Showerjack!!"
"Dude!? What the %^&* is wrong with you?"

2) "That was a nasty showerjack; I'm going to go soak his underwear in capsaicin."

showerjack by Greevey McSeamus October 17, 2008

Showerjack 

To steal shower first even though another roommate or family member is getting ready for a shower, leaving them to wait impatiently for you in their bathrobe or towel.

Just as Tina prepared to enter the bathroom, she could hear that her roommate had showerjacked, and was stuck waiting for another hour.

Showerjack by Snoopy Snoopy Poop Dogg April 25, 2011