Appears 3 times in the Quran. (Root: زيد)
  1. Surely, those who disbelieve after their believing, then increase in unbelief, their repentance shall not be accepted, and these are they that go astray.

  2. Surely (as for) those who believe then disbelieve, again believe and again disbelieve, then increase in disbelief, Allah will not forgive them nor guide them in the (right) path.

  3. And they remained in their cave three hundred years and (some) add (another) nine.