rapper

from The Century Dictionary.

• noun One who raps or knocks; specifically, a spirit-rapper.
• noun The knocker of a door.
• noun In coal-mining, a lever with a hammer attached at one end, placed at the mouth of a shaft or incline for giving signals to the banksman, by rapping on an iron plate.
• noun An extravagant oath or lie; a “whopper.” See to rap out , under rap, transitive verb

from the GNU version of the Collaborative International Dictionary of English.

• noun One who, or that which, raps or knocks; specifically, the knocker of a door.
• noun Slang A forcible oath or lie.
• noun A musician specializing in rap music.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun One who, or that which, raps or knocks; specifically, the knocker of a door.
• noun A performer of rap music
• noun A forcible oath or lie.
• noun obsolete: Scottish English word for "sword."
• noun A flexible strip of metal, 45-60cm long, with handles at each end, used for Northumbrian rapper sword dancing.
• noun A mechanical, or later electric, signalling device formerly used in the mines of north-eastern England to signal to the engineman that the cages carrying men or coals up and down the shaft were ready to be raised or lowered.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a device (usually metal and ornamental) attached by a hinge to a door
• noun someone who performs rap music