Source : Webster's Revised Unabridged Dictionary (1913)

Unballasted \Un*bal"last*ed\, a.
   1. [Properly p. p. unballast.] Freed from ballast; having
      discharged ballast.

   2. [Pref. un- not + ballasted.] Not furnished with ballast;
      not kept steady by ballast; unsteady; as, unballasted
      vessels; unballasted wits.

            Unballasted by any sufficient weight of plan. --De
                                                  Quincey.