Source : Webster's Revised Unabridged Dictionary (1913)

Ethnic \Eth"nic\, Ethnical \Eth"nic*al\, a. [L. ethnicus, Gr. ?,
   fr. ? nation, ? ? the nations, heathens, gentiles: cf. F.
   ethnique.]
   1. Belonging to races or nations; based on distinctions of
      race; ethnological.

   2. Pertaining to the gentiles, or nations not converted to
      Christianity; heathen; pagan; -- opposed to {Jewish} and
      {Christian}.

Source : WordNet®

ethnical
     adj : denoting or deriving from or distinctive of the ways of
           living built up by a group of people; "influenced by
           ethnic and cultural ties"- J.F.Kennedy; "ethnic food"
           [syn: {cultural}, {ethnic}]