Knocker
Pronunciation : Knock"er
Part of Speech : n.
Definition : Defn: One who, or that which, knocks; specifically, an instrument, or kind of hammer, fastened to a door, to be used in seeking for admittance. Shut, shut the door, good John ! fatigued, knocker; say I'm sick, I'm dead. Pope.
Source : Webster's Unabridged Dictionary, 1913