Source : Webster's Revised Unabridged Dictionary (1913)

Precociousness \Pre*co"cious*ness\, Precocity \Pre*coc"i*ty\, n.
   [Cf. F. pr['e]cocit['e].]
   The quality or state of being precocious; untimely ripeness;
   premature development, especially of the mental powers;
   forwardness.

         Saucy precociousness in learning.        --Bp.
                                                  Mannyngham.

         That precocity which sometimes distinguishes uncommon
         genius.                                  --Wirt.

Source : WordNet®

precocity
     n : intelligence achieved far ahead of normal developmental
         schedules [syn: {precociousness}]