Source : Webster's Revised Unabridged Dictionary (1913)

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.

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

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

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

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

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

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

   {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.