To strike with the open hand or with something flat: as, to slap one on the back; to slap a child on the hand.To strike with; bring upon or against something with a blow.n. A blow given with the open hand, or with something flat.With sudden and violent force; plump; suddenly.First-rate; of the best; “slap-up.”n. A narrow pass between two hills.n. A breach in a wall, hedge, or fence; a gap.n. A gap in the edge of a knife, etc.To break into gaps; break out (an opening), as in a solid wall.An obsolete variant of slop.