look up any word, like cunt:
 
1.
nasty, horrible, disgusting
urgh, i had to open the window, cuz the car smelt gacky as fuck
by mikepacker88 October 14, 2007
 
2.
something that makes you gack, often yucky
the food was gacky.
by Pookett May 18, 2007
 
3.
a nickname for someone that does meth. from the word "gacked"
hey gacky, are you gacked ouy today?
by S. 22nd street October 18, 2006
 
4.
uncoordinated, unco, sloppy, as in when running.

also used to describe something that is gack-like, gooey, sloppy.
hey man, i suck at running. i'm so gacky.

ew that's gacky!
by mez05 September 19, 2006