Basically an updated version of "shooting yourself in the foot" or "fucking yourself over."
Taken from the miserable campaign of Jung-Suk Ryu for city Counsillor in Edmonton, AB.

Also:
jungsuker: the individual junsuking oneself.
jungsukery: the act of jungsuking.
"When Jimmy puked at the bar, he totally jungsuked his chances with that that chick."
by RAH October 21, 2004
Get the jungsuked mug.