Source : Webster's Revised Unabridged Dictionary (1913)

Preternatural \Pre`ter*nat"u*ral\ (?; 135), a. [Pref. preter +
   natural.]
   Beyond of different from what is natural, or according to the
   regular course of things, but not clearly supernatural or
   miraculous; strange; inexplicable; extraordinary; uncommon;
   irregular; abnormal; as, a preternatural appearance; a
   preternatural stillness; a preternatural presentation (in
   childbirth) or labor.

         This vile and preternatural temper of mind. --South.

   Syn: See {Supernatural}.

Source : WordNet®

preternatural
     adj 1: surpassing the ordinary or normal; "Beyond his preternatural
            affability there is some acid and some steel"- George
            Will
     2: existing outside of or not in accordance with nature; "find
        transcendental motives for sublunary action"-Aldous Huxley
        [syn: {nonnatural}, {otherworldly}, {transcendental}]