The Collaborative International Dictionary of English v.0.48:

Dominant \Dom"i*nant\, a. [L. dominans, -antis, p. pr. of
   dominari: cf. F. dominant. See Dominate.]
   Ruling; governing; prevailing; controlling; predominant; as,
   the dominant party, church, spirit, power.
   [1913 Webster]

         The member of a dominant race is, in his dealings with
         the subject race, seldom indeed fraudulent, . . . but
         imperious, insolent, and cruel.          --Macaulay.
   [1913 Webster]

   Dominant estate or Dominant tenement (Law), the estate to
      which a servitude or easement is due from another estate,
      the estate over which the servitude extends being called
      the servient estate or tenement. --Bouvier. --Wharton's
      Law Dict.

   Dominant owner (Law), one who owns lands on which there is
      an easement owned by another.
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   Syn: Governing; ruling; controlling; prevailing; predominant;
        ascendant.
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