conk

Etymology 1

Variant or figurative use of conch. Attested since the nineteenth century.

noun

1. The shelf- or bracket-shaped fruiting body of a bracket fungus (also called a shelf fungus), i.e. a mushroom growing off a tree trunk.
2. (slang) A nose, especially a large one.
3. Alternative spelling of conch

verb

1. (slang) To hit, especially on the head.

Etymology 2

From congolene, the brand name of a hair-straightening product.

noun

1. (US, dated) A hairstyle involving the chemical straightening and styling of kinky hair.

verb

1. (US, dated) To chemically straighten tightly curled hair.
   The barbecue cook, wearing a dirty white apron, his conked hair reddish and metallic in the pale sun, and a cigarette between his lips, stood in the doorway, watching them. 1957, James Baldwin, “Sonny’s Blues”, in Going to Meet the Man, Dial, published 1965

Etymology 3

Unknown. Attested since the early twentieth century.

verb

1. (colloquial, often with out) To fail or show signs of failing, cease operating, break down.
   Therefore, have two or more engines, so that there is still some power left if one engine conks. 1921, Australian Aero Clubs, Sea, Land and Air, volume 3, page 310
   I watch television when it's playing, but it done conked out. Everything is conked out. 1983, Walli Leff, Marilyn Haft, Time without Work, page 93
2. (colloquial, often with out) To become unconscious.