Source : Webster's Revised Unabridged Dictionary (1913)

Nomothetic \Nom`o*thet"ic\, Nomothetical \Nom`o*thet"ic*al\, a.
   [Gr. ?.]
   Legislative; enacting laws; as, a nomothetical power. [R.]
   --Bp. Barlow.

Source : WordNet®

nomothetic
     adj : relating to or involving the search for abstract universal
           principles [ant: {idiographic}]