The Collaborative International Dictionary of English v.0.48:

Lability \La*bil"i*ty\, n.
   1. Liability to lapse, err, or apostatize. [Archaic]
      --Coleridge.
      [1913 Webster]

   2. The property of changing readily.
      [PJC]

   3. (Chem.) The property of being labile[3]; -- of chemical
      compounds; as, the lability of some natural products makes
      them difficult to isolate and identify.
      [PJC]