Source : Webster's Revised Unabridged Dictionary (1913)

Fiber \Fi"ber\, Fibre \Fi"bre\,, n. [F. fibre, L. fibra.]
   1. One of the delicate, threadlike portions of which the
      tissues of plants and animals are in part constituted; as,
      the fiber of flax or of muscle.

   2. Any fine, slender thread, or threadlike substance; as, a
      fiber of spun glass; especially, one of the slender
      rootlets of a plant.

   3. Sinew; strength; toughness; as, a man of real fiber.

            Yet had no fibers in him, nor no force. --Chapman.

   4. A general name for the raw material, such as cotton, flax,
      hemp, etc., used in textile manufactures.

   {Fiber gun}, a kind of steam gun for converting, wood, straw,
      etc., into fiber. The material is shut up in the gun with
      steam, air, or gas at a very high pressure which is
      afterward relieved suddenly by letting a lid at the muzzle
      fly open, when the rapid expansion separates the fibers.
      

   {Fiber plants} (Bot.), plants capable of yielding fiber
      useful in the arts, as hemp, flax, ramie, agave, etc.

Source : WordNet®

fibre
     n 1: a slender and greatly elongated solid substance [syn: {fiber}]
     2: the inherent complex of attributes that determine a persons
        moral and ethical actions and reactions; "education has
        for its object the formation of character"- Herbert
        Spencer [syn: {character}, {fiber}]
     3: a leatherlike material made by compressing layers of paper
        or cloth [syn: {fiber}, {vulcanized fiber}]