scottish slang to describe the unfortunate one with an under-bite.
"sham gabbit"=someone who,s lower jaw protrudes further than their top jaw therefore producing an over-bite... flip side being "gabbit sham" =an over bite, where the upper jaw protrudes over the lower jaw..
"his sham gabbit was so blatent! and he had described himself as handsome!!! apparently not so!! "