(1):

(n.) The sound made by the sudden fall or blow of a heavy body, as of a hammer, or the like.

(2):

(n.) A blow or knock, as with something blunt or heavy; a heavy fall.

(3):

(v. i.) To give a thump or thumps; to strike or fall with a heavy blow; to pound.

(4):

(v. t.) To strike or beat with something thick or heavy, or so as to cause a dull sound.