When someone jumps in on a joke or a piss-take and trys to add to it or take it over. Normally a sad person who has no life or the usual cunt who just needs attention that othwise he/she would go un-noticed.
1st person: Hey did you hear the one about...etc,etc
Sad lonely cunt: Haha yeh ive heard this (then trys to take over joke or adds to it.
1st person: Oh great, a Joke Jacker, what a cunt
Sad lonely cunt: Haha yeh ive heard this (then trys to take over joke or adds to it.
1st person: Oh great, a Joke Jacker, what a cunt
by kevtucks January 29, 2009

Anyone who goes into a bathroom, picks up some random person's shit they found in the toilet, and runs away with it.
by Bruh.........er February 25, 2015

*Fap* *Fap* *Fap* "WHAT THE HELL DUDE" "What?" "WE ARE AT GRANDMA'S FUNERAL" "So?" "YOU ARE BEING A JACKER BOY RIGHT NOW?" "Well sorry, I can't control my urge to splurge"
by Bin Laden's Meaty pussy October 14, 2016

by Ameena Turnee July 18, 2010

One that partakes in Steady Jacking
by Capt. Load Chucker March 1, 2008

Lil Wayne is a Swagger Jacker, he copies B.I.G., 2Pac, Jay-Z (Jay-Z the most, and he had beef with him lol), His dad, and 2 other rappers, and even an R&B Singer! Best Rapper Alive my ass!
by fuck wayne dick riders August 14, 2009
