Short form of the word Gnarley Used as a word of encouragement as if to say "right on", "awesome" etc.
Person one: Bro, I just found a hundred dollar bill on the sidewalk!
Person two: Gnar!
or
Person one: I met two chicks at the bar last night and we had a threesome!
Person two: Gnar!
Person two: Gnar!
or
Person one: I met two chicks at the bar last night and we had a threesome!
Person two: Gnar!
by Mad Lols March 08, 2011