(1):

(n.) A thump; a heavy blow.

(2):

(v. t.) To strike, as with or against anything large or solid; to thump; as, to bump the head against a wall.

(3):

(n.) A swelling or prominence, resulting from a bump or blow; a protuberance.

(4):

(n.) One of the protuberances on the cranium which are associated with distinct faculties or affections of the mind; as, the bump of "veneration;" the bump of "acquisitiveness."

(5):

(n.) The act of striking the stern of the boat in advance with the prow of the boat following.

(6):

(v. i.) To make a loud, heavy, or hollow noise, as the bittern; to boom.

(7):

(n.) The noise made by the bittern.

(8):

(v. i.) To come in violent contact with something; to thump.