conk out

• konk out

Possibly an onomatopoeic imitation of the sound of a stalling internal combustion engine. Possibly coined by British motorcyclists circa 1910.

conk out (third-person singular simple present conks out, present participle conking out, simple past and past participle conked out)

1. (intransitive, informal) To fall fast asleep; to sleep soundly.

   Synonym: zonk out

   He wasn't there, just the dog, conked out on the porch.

2. (intransitive, informal) To stop functioning.

   The old car conked out halfway up the hill.

   • 2016, Joseph Henrich, chapter 5, in The Secret of Our Success […] , Princeton: Princeton University Press, →ISBN:

     So, if you want to race your dog, plan a 25-kilometer race on a hot summer day. He'll conk out.

3. (intransitive, informal) To die.

   He lived to be 90, then conked out in his sleep.