The act of inserting a "Purim" (the Jewish counterpart for Halloween) "Grogger" (noise maker) in
one's anus while leaving the
handle protruded. Another will grab the protruded handle and await the cantor's reading. As the cantor says "Haman" (the evil
man) the handle-holder and the Butt Grogger will turn oppositely; thus emanating the muffled-clicking sound constituting the "Butt Grogging".