conk out in WordNet English dictionary

1. stop operating or functioning
   "The engine finally went"; "The car died on the road"; "The bus we travelled in broke down on the way to town"; "The coffee maker broke"; "The engine failed on the way to town"; "her eyesight went after the accident"
   fail  go bad  give way  die  give out  conk out  go  break  break down 
   
2. use up all one's strength and energy and stop working
   "At the end of the march, I pooped out"
   poop out  peter out  run down  run out  conk out 
   

conk out in English Wiktionary