Source : Webster's Revised Unabridged Dictionary (1913)

Fold \Fold\, n. [From {Fold}, v. In sense 2 AS. -feald, akin to
   fealdan to fold.]
   1. A doubling,esp. of any flexible substance; a part laid
      over on another part; a plait; a plication.

            Mummies . . . shrouded in a number of folds of
            linen.                                --Bacon.

            Folds are most common in the rocks of mountainous
            regions.                              --J. D. Dana.

   2. Times or repetitions; -- used with numerals, chiefly in
      composition, to denote multiplication or increase in a
      geometrical ratio, the doubling, tripling, etc., of
      anything; as, fourfold, four times, increased in a
      quadruple ratio, multiplied by four.

   3. That which is folded together, or which infolds or
      envelops; embrace.

            Shall from your neck unloose his amorous fold.
                                                  --Shak.

   {Fold net}, a kind of net used in catching birds.