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1.
gnack gnack : melon/skull/head/back of the neck/forhead/face.

-- but only called this when you pull a retarded maneuver to actually fall on your skull..
ie: when i dropped in from the top of the over vert cradle in scarnation skate park i fell straight to my gnack gnack..
by Oneshot Jonny March 25, 2004
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