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1.
An old game by the name of Monster Rancher 1 & 2 used to have a small, fat, boneless creature called a Gaboo.

Therefore, it became commonplace by its players to call anyone short and fat a “gaboo”, a “gaboo” can also be any person that is particularly gutless and cowardly.
"Jim is such a fucking gaboo."
by John Delonge April 08, 2006