Source : Webster's Revised Unabridged Dictionary (1913)

Folding \Fold"ing\, n.
   1. The act of making a fold or folds; also, a fold; a
      doubling; a plication.

            The lower foldings of the vest.       --Addison.

   2. (Agric.) The keepig of sheep in inclosures on arable land,
      etc.

   {Folding boat}, a portable boat made by stretching canvas,
      etc., over jointed framework, used in campaigning, and by
      tourists, etc. --Ham. Nav. Encyc.

   {Folding chair}, a chair which may be shut up compactly for
      carriage or stowage; a camp chair.

   {Folding door}, one of two or more doors filling a single and
      hung upon hinges.

Source : WordNet®

folding door
     n : an interior door that opens by folding back in sections
         (rather than by swinging on hinges) [syn: {accordion door}]