Definitions of knocker:
- noun: a device (usually metal and ornamental) attached by a hinge to a door
- noun: a person who knocks (as seeking to gain admittance)
Example: "Open the door and see who the knocker is"
- noun: (Yiddish) a big shot who knows it and acts that way; a boastful immoderate person
- noun: either of two soft fleshy milk-secreting glandular organs on the chest of a woman
- noun: one who disparages or belittles the worth of something
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