look up any word, like sparkle pony:
 
1.
Either "Good Luck, Fine Friend" or "Good Luck, Fuck-Face" depending on context and the person being spoken to.

Often used in online games.
"Dude, I am totally going to go talk to that hot chick over there."
"GLFF."
by aidan64 October 26, 2009
 
2.
good looking from far away
damn that chick on the bike was glff but up close she was fugly
by Dr. Killer Rabbit August 25, 2009