Nouns

(n)knocker(Yiddish) a big shot who knows it and acts that way; a boastful immoderate person
(n)knockera person who knocks (as seeking to gain admittance)“open the door and see who the knocker is”
(n)detractor, disparager, depreciator, knockerone who disparages or belittles the worth of something
(n)breast, bosom, knocker, boob, tit, tittyeither of two soft fleshy milk-secreting glandular organs on the chest of a woman
(n)knocker, doorknocker, rappera device (usually metal and ornamental) attached by a hinge to a door