Source : Webster's Revised Unabridged Dictionary (1913)

Volatileness \Vol"a*tile*ness\, Volatility \Vol`a*til"i*ty\, n.
   [Cf. F. volatilit['e].]
   Quality or state of being volatile; disposition to evaporate;
   changeableness; fickleness.

   Syn: See {Levity}.

Source : WordNet®

volatility
     n 1: the property of changing readily from a solid or liquid to a
          vapor
     2: the trait of being unpredictably irresolute; "the volatility
        of the market drove many investors away" [syn: {unpredictability}]
     3: being easily excited [syn: {excitability}, {excitableness}]