The Collaborative International Dictionary of English v.0.48:

Yore \Yore\ (y[=o]r), adv. [OE. [yogh]ore, yare, [yogh]are, AS.
   ge['a]ra;akin to ge['a]r a year, E. year. [root]204. See
   Year.]
   In time long past; in old time; long since. [Obs. or Poetic]
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         As it hath been of olde times yore.      --Chaucer.
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         Which though he hath polluted oft and yore,
         Yet I to them for judgment just do fly.  --Spenser.
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   Of yore, of old time; long ago; as, in times or days of
      yore. "But Satan now is wiser than of yore." --Pope.
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            Where Abraham fed his flock of yore.  --Keble.
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WordNet (r) 3.0 (2006):

yore
    n 1: time long past