The Collaborative International Dictionary of English v.0.48:

Stool \Stool\, n. [L. stolo. See Stolon.] (Hort.)
   A plant from which layers are propagated by bending its
   branches into the soil. --P. Henderson.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Stool \Stool\, v. i. (Agric.)
   To ramfy; to tiller, as grain; to shoot out suckers. --R. D.
   Blackmore.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Stool \Stool\, n. [AS. st[=o]l a seat; akin to OFries. & OS.
   st[=o]l, D. stoel, G. stuhl, OHG. stuol, Icel. st[=o]ll, Sw.
   & Dan. stol, Goth. st[=o]ls, Lith. stalas a table, Russ.
   stol'; from the root of E. stand. [root]163. See Stand, and
   cf. Fauteuil.]
   1. A single seat with three or four legs and without a back,
      made in various forms for various uses.
      [1913 Webster]

   2. A seat used in evacuating the bowels; hence, an
      evacuation; a discharge from the bowels.
      [1913 Webster]

   3. A stool pigeon, or decoy bird. [U. S.]
      [1913 Webster]

   4. (Naut.) A small channel on the side of a vessel, for the
      dead-eyes of the backstays. --Totten.
      [1913 Webster]

   5. A bishop's seat or see; a bishop-stool. --J. P. Peters.
      [1913 Webster]

   6. A bench or form for resting the feet or the knees; a
      footstool; as, a kneeling stool.
      [1913 Webster]

   7. Material, such as oyster shells, spread on the sea bottom
      for oyster spat to adhere to. [Local, U.S.]
      [1913 Webster]

   Stool of a window, or Window stool (Arch.), the flat
      piece upon which the window shuts down, and which
      corresponds to the sill of a door; in the United States,
      the narrow shelf fitted on the inside against the actual
      sill upon which the sash descends. This is called a window
      seat when broad and low enough to be used as a seat.

   Stool of repentance, the cuttystool. [Scot.]

   Stool pigeon, a pigeon used as a decoy to draw others
      within a net; hence, a person used as a decoy for others.
      [1913 Webster]

WordNet (r) 3.0 (2006):

stool
    n 1: a simple seat without a back or arms
    2: solid excretory product evacuated from the bowels [syn:
       fecal matter, faecal matter, feces, faeces, BM,
       stool, ordure, dejection]
    3: (forestry) the stump of a tree that has been felled or headed
       for the production of saplings
    4: a plumbing fixture for defecation and urination [syn:
       toilet, can, commode, crapper, pot, potty,
       stool, throne]
    v 1: lure with a stool, as of wild fowl
    2: react to a decoy, of wildfowl
    3: grow shoots in the form of stools or tillers [syn: stool,
       tiller]
    4: have a bowel movement; "The dog had made in the flower beds"
       [syn: stool, defecate, shit, take a shit, take a
       crap, ca-ca, crap, make]