Source : Webster's Revised Unabridged Dictionary (1913)

Dysteleology \Dys*te`le*ol"o*gy\, n. [Pref. dys- + teleology.]
   (Biol.)
   The doctrine of purposelessness; a term applied by Haeckel to
   that branch of physiology which treats of rudimentary organs,
   in view of their being useless to the life of the organism.

         To the doctrine of dysteleology, or the denial of final
         causes, a proof of the real existence of such a thing
         as instinct must necessarily be fatal.   --Word
                                                  (Dynamic
                                                  Sociology).