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Etymology 1
. Related to.

Verb

 * 1) to go out, to die out, to wink out (of light, fire)
 * 2)  to grow empty, to grow lifeless (of look, eyes)
 * 3)  to die down, to grow weak, to diminish

Etymology 2
or, related to. Possibly related to Etymology 1.

Verb

 * 1) to go bad, to spoil (of food)
 * 2)  to stagnate