The Collaborative International Dictionary of English v.0.48:

Thither \Thith"er\, adv. [OE. thider, AS. [eth]ider; akin to E.
   that; cf. Icel. [thorn]a[eth]ra there, Goth.
   [thorn]a[thorn]r[=o] thence. See That, and The.]
   1. To that place; -- opposed to hither.
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            This city is near; . . . O, let me escape thither.
                                                  --Gen. xix.
                                                  20.
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            Where I am, thither ye can not come.  --John vii.
                                                  34.
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   2. To that point, end, or result; as, the argument tended
      thither.
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   Hither and thither, to this place and to that; one way and
      another.
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   Syn: There.

   Usage: Thither, There. Thither properly denotes motion
          toward a place; there denotes rest in a place; as, I
          am going thither, and shall meet you there. But
          thither has now become obsolete, except in poetry, or
          a style purposely conformed to the past, and there is
          now used in both senses; as, I shall go there
          to-morrow; we shall go there together.
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The Collaborative International Dictionary of English v.0.48:

Thither \Thith"er\, a.
   1. Being on the farther side from the person speaking;
      farther; -- a correlative of hither; as, on the thither
      side of the water. --W. D. Howells.
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   2. Applied to time: On the thither side of, older than; of
      more years than. See Hither, a. --Huxley.
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WordNet (r) 3.0 (2006):

thither
    adv 1: to or toward that place; away from the speaker; "go there
           around noon!" [syn: there, thither] [ant: here,
           hither]