Source : Webster's Revised Unabridged Dictionary (1913)

Hierarchal \Hi"er*arch`al\, Hierarchic \Hi`er*arch"ic\, a.
   Pertaining to a hierarch. ``The great hierarchal standard.''
   --Milton.

Source : WordNet®

hierarchal
     adj : classified according to various criteria into successive
           levels or layers; "it has been said that only a
           hierarchical society with a leisure class at the top
           can produce works of art"; "in her hierarchical set of
           values honesty comes first" [syn: {hierarchical}, {hierarchic}]
           [ant: {nonhierarchical}]