Cut deeply (8)
(Other definitions for lacerate that I've seen before include "Tear roughly, cut jaggedly" , "Tear or make deep cuts" , "Deeply cut (flesh, skin)" , "Cut, leaving jagged edges" , "Tear or gash roughly" .)
(Other definitions for slash that I've seen before include "Oblique stroke" , "something between a month and a year" , "Legendary guitarist" , "rent" , "Cut as with a sword - /" .)