Bang  —n. 1 loud short sound. 2 sharp blow. 3 coarse slang act of sexual intercourse. 4 us fringe cut straight across the forehead. —v. 1 strike or shut noisily (banged the door). 2 (cause to) make a bang. 3 coarse slang have sexual intercourse (with). —adv. 1 with a bang. 2 colloq. Exactly (bang in the middle).  bang on colloq. Exactly right. Go bang 1 shut noisily. 2 explode. 3 (as bang goes etc.) Colloq. Be suddenly lost (bang go my hopes). [imitative]