1 definition by Mysterious Jeff

One who does things for no apparent reason, without understanding their situation.

A formal greeting among friends

Someone who has what we call "Sugar tourettes", on a sugar high and says things at random
Friend -Hey jeff i heard you were planning on studying later with jamey right?
Jeff- GAK!

Hey jeff whats up? GAK!

Hey jamesy poo, i got you a valentines day present. GAK! SHAMAGALA
by Mysterious Jeff February 13, 2009
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