Source : Webster's Revised Unabridged Dictionary (1913)

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.]

            If weather be fair and tidy.          --Tusser.

   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.

            A tidy man, that tened [injured] me never. --Piers
                                                  Plowman.

Source : WordNet®

tidy
     adj 1: marked by good order and cleanliness in appearance or
            habits; "a tidy person"; "a tidy house"; "a tidy mind"
            [ant: {untidy}]
     2: (used of hair) neat and tidy; "a nicely kempt beard" [syn: {kempt},
         {trim}]
     3: large in amount or extent or degree; "it cost a considerable
        amount"; "a goodly amount"; "received a hefty bonus"; "a
        respectable sum"; "a tidy sum of money"; "a sizable
        fortune" [syn: {goodly}, {goodish}, {hefty}, {respectable},
         {sizable}, {sizeable}]
     n : receptacle that holds odds and ends (as sewing materials)
     [also: {tidied}, {tidiest}, {tidier}]

tidy
     v : put (things or places) in order; "Tidy up your room!" [syn:
         {tidy up}, {clean up}, {neaten}, {straighten}, {straighten
         out}, {square away}]
     [also: {tidied}, {tidiest}, {tidier}]

tidier
     See {tidy}