to have at vantage

Vantage \Van"tage\ (v[.a]n"t[asl]j; 48), n. [Aphetic form of OE.
   avantage, fr. F. avantage. See {Advantage}.]
   1. Superior or more favorable situation or opportunity; gain;
      profit; advantage. [R.]
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            O happy vantage of a kneeling knee!   --Shak.
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   2. A position offering a superior view of a scene or
      situation; -- used literally and figuratively; as, from
      the vantage of hindsight; also called {vantage point}.
      [PJC]

   3. (Tennis) The first point scored after deuce; advantage[5].
      [Brit.]
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   Note: When the server wins this point, it is called vantage
         in; when the receiver, or striker out, wins, it is
         called vantage out.
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   {To have at vantage}, to have the advantage of; to be in a
      more favorable condition than. "He had them at vantage,
      being tired and harassed with a long march." --Bacon.

   {Vantage ground}, superiority of state or place; the place or
      condition which gives one an advantage over another. "The
      vantage ground of truth." --Bacon.
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            It is these things that give him his actual
            standing, and it is from this vantage ground that he
            looks around him.                     --I. Taylor.
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