n., v., & adv.
n. 1 a dull-sounding blow or collision. 2 a swelling or dent caused by this. 3 an uneven patch on a road, field, etc. 4 Phrenol. any of various prominences on the skull thought to indicate different mental faculties. 5 (in narrow-river races where boats make a spaced start one behind another) the point at which a boat begins to overtake (and usu. touches) the boat ahead, thereby defeating it. 6 Aeron. a an irregularity in an aircraft's motion. b a rising air current causing this.
v. 1 a tr. hit or come against with a bump. b intr. (of two objects) collide. 2 intr. (foll. by against, into) hit with a bump; collide with. 3 tr. (often foll. by against, on) hurt or damage by striking (bumped my head on the ceiling; bumped the car while parking). 4 intr. (usu. foll. by along) move or travel with much jolting (we bumped along the road). 5 tr. (in a boat-race) gain a bump against. 6 tr. US displace, esp. by seniority.
adv. with a bump; suddenly; violently. bump into colloq. meet by chance. bump off sl. murder. bump up colloq. increase (prices etc.).
[ 16th c., imit.: perh. f. Scand. ]