Adjective; a label with 21st century colloquial English roots, the term is used to highlight stupidity in those whom it brands, mixing the term 'wahey- gutted!' with the adjective 'wahey! Wanker'.
"I just fell down the stairs in the Science block at school"
*N.B. - For variation or more formal occasions one may instead inform the idiot in question: "You just earned yourself a gutwank".