adv. [ Slap + dash. ] 1. In a bold, careless manner; at random. [ Colloq. ] [ 1913 Webster ]
2. With a slap; all at once; slap. [ Colloq. ] Prior. [ 1913 Webster ]
v. t. To apply, or apply something to, in a hasty, careless, or rough manner; to roughcast; as, to slapdash mortar or paint on a wall, or to slapdash a wall. [ Colloq. ] Halliwell. [ 1913 Webster ]