knocker
[noun]
Synonyms: critic, aristarch, carper, caviler, criticizer, faultfinder, momus, smellfungus, Zoilus

[TahlilGaran] English Synonym Dictionary ▲

I. door‧knock‧er /ˈdɔːˌnɒkə $ ˈdɔːrˌnɑːkər/ (also knocker) noun [countable]
a heavy metal ring or bar on a door that you use to knock with

[TahlilGaran] Dictionary of Contemporary English ▲

II. knock‧er /ˈnɒkə $ ˈnɑːkər/ noun [countable]

1. a piece of metal on an outside door of a house that you hit against the door to attract the attention of the people inside ⇒ doorknocker

2. knockers [plural] spoken not polite an offensive word meaning a woman’s breasts

[TahlilGaran] Dictionary of Contemporary English ▲