knocker

Etymology

knock +‎ -er

Pronunciation

• Rhymes: -ɒkə(r)

Noun

knocker (plural knockers)

1. A device, usually hinged with a striking plate, used for knocking on a door.
2. A person who knocks (denigrates) something.
3. (slang) (usually in the plural) A woman's breasts.
4. (particularly in Cardigan etc. in South Wales, 18th to 19th century) A dwarf, goblin, or sprite imagined to dwell in mines and to indicate the presence of ore by knocking.
5. (pinball) A mechanical device in a pinball table that produces a loud percussive noise.
   • 1963, Harper's magazine (volume 226)

     A good game needs color, lights, bells, gongs, and knockers, all to assure the player he is making progress […]

6. (dated, slang) A person who is strikingly handsome or otherwise admirable; a stunner.
7. A large cockroach, especially Blabera gigantea, of semitropical America, which is able to produce a loud knocking sound.
8. (geology) A large, boulder-shaped outcrop of bedrock in an otherwise low-lying landscape, chiefly associated with a mélange.