knocker

(Yiddish) a big shot who knows it and acts that way; a boastful immoderate person

a person who knocks (as seeking to gain admittance); "open the door and see who the knocker is"

one who disparages or belittles the worth of something

either of two soft fleshy milk-secreting glandular organs on the chest of a woman

a device (usually metal and ornamental) attached by a hinge to a door