The Collaborative International Dictionary of English v.0.48:

Tidy \Ti"dy\, a. [Compar. Tidier; superl. Tidiest.] [From
   Tide time, season; cf. D. tijdig timely, G. zeitig, Dan. &
   Sw. tidig.]
   1. Being in proper time; timely; seasonable; favorable; as,
      tidy weather. [Obs.]
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            If weather be fair and tidy.          --Tusser.
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   2. Arranged in good order; orderly; appropriate; neat; kept
      in proper and becoming neatness, or habitually keeping
      things so; as, a tidy lass; their dress is tidy; the
      apartments are well furnished and tidy.
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            A tidy man, that tened [injured] me never. --Piers
                                                  Plowman.
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