The Collaborative International Dictionary of English v.0.48:

Wool \Wool\ (w[oo^]l), n. [OE. wolle, wulle, AS. wull; akin to
   D. wol, OHG. wolla, G. wolle, Icel. & Sw. ull, Dan. uld,
   Goth, wulla, Lith. vilna, Russ. volna, L. vellus, Skr.
   [=u]r[.n][=a] wool, v[.r] to cover. [root]146, 287. Cf.
   Flannel, Velvet.]
   [1913 Webster]
   1. The soft and curled, or crisped, species of hair which
      grows on sheep and some other animals, and which in
      fineness sometimes approaches to fur; -- chiefly applied
      to the fleecy coat of the sheep, which constitutes a most
      essential material of clothing in all cold and temperate
      climates.
      [1913 Webster]

   Note: Wool consists essentially of keratin.
         [1913 Webster]

   2. Short, thick hair, especially when crisped or curled.
      [1913 Webster]

            Wool of bat and tongue of dog.        --Shak.
      [1913 Webster]

   3. (Bot.) A sort of pubescence, or a clothing of dense,
      curling hairs on the surface of certain plants.
      [1913 Webster]

   Dead pulled wool, wool pulled from a carcass.

   Mineral wool. See under Mineral.

   Philosopher's wool. (Chem.) See Zinc oxide, under Zinc.


   Pulled wool, wool pulled from a pelt, or undressed hide.

   Slag wool. Same as Mineral wool, under Mineral.

   Wool ball, a ball or mass of wool.

   Wool burler, one who removes little burs, knots, or
      extraneous matter, from wool, or the surface of woolen
      cloth.

   Wool comber.
      (a) One whose occupation is to comb wool.
      (b) A machine for combing wool.

   Wool grass (Bot.), a kind of bulrush (Scirpus Eriophorum)
      with numerous clustered woolly spikes.

   Wool scribbler. See Woolen scribbler, under Woolen, a.


   Wool sorter's disease (Med.), a disease, resembling
      malignant pustule, occurring among those who handle the
      wool of goats and sheep.

   Wool staple, a city or town where wool used to be brought
      to the king's staple for sale. [Eng.]

   Wool stapler.
      (a) One who deals in wool.
      (b) One who sorts wool according to its staple, or its
          adaptation to different manufacturing purposes.

   Wool winder, a person employed to wind, or make up, wool
      into bundles to be packed for sale.
      [1913 Webster]

WordNet (r) 3.0 (2006):

wool grass
    n 1: sedge of eastern North America having numerous clustered
         woolly spikelets [syn: wool grass, Scirpus cyperinus]
    2: grass often cultivated for its long white-ribbed leaves and
       large plumes resembling those of pampas grass [syn: Ravenna
       grass, wool grass, Erianthus ravennae]