The Collaborative International Dictionary of English v.0.48:
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.]
[1913 Webster]
O happy vantage of a kneeling knee! --Shak.
[1913 Webster]
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.]
[1913 Webster]
Note: When the server wins this point, it is called vantage
in; when the receiver, or striker out, wins, it is
called vantage out.
[1913 Webster]
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.
[1913 Webster]
It is these things that give him his actual
standing, and it is from this vantage ground that he
looks around him. --I. Taylor.
[1913 Webster]