A B.A.M.F.W. is a Bad Ass Mother Fucking Wizard relating to all the awsome peeps in JK Rowling's books, the Harry Potter series. These include Harry, Dumbledore and suprisingly Neville in the 7th book and in the 8th movie.
Holy shit did magic just come out of these guys twigs and kill her
by jk rowling, harry potter, July 17, 2011