Definition of conking:
(v) :
(colloquial, often with out) To fail or show signs of failing, cease operating, break down.
(v) :
(colloquial, often with out) To become unconscious.
(v) :
(slang) To hit, especially on the head.
(n) :
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.
(n) :
(slang) A nose, especially a large one.
(v) :
(US, dated) To chemically straighten tightly curled hair.