Source : Webster's Revised Unabridged Dictionary (1913)

   1. (Anat.) A glandular organ which excretes urea and other
      waste products from the animal body; a urinary gland.

   Note: In man and in other mammals there are two kidneys, one
         each side of vertebral column in the back part of the
         abdomen, each kidney being connected with the bladder
         by a long tube, the ureter, through which the urine is
         constantly excreted into the bladder to be periodically
         discharged.

   2. Habit; disposition; sort; kind. --Shak.

            There are in later other decrees, made by popes of
            another kidney.                       --Barrow.

            Millions in the world of this man's kidney.
                                                  --L'Estrange.

            Your poets, spendthrifts, and other fools of that
            kidney, pretend, forsooth, to crack their jokes on
            prudence.                             --Burns.

   Note: This use of the word perhaps arose from the fact that
         the kidneys and the fat about them are an easy test of
         the condition of an animal as to fatness. ``Think of
         that, -- a man of my kidney; -- . . . as subject to
         heat as butter.'' --Shak.

   3. A waiter. [Old Cant] --Tatler.

   {Floating kidney}. See {Wandering kidney}, under {Wandering}.
      

   {Kidney bean} (Bot.), a sort of bean; -- so named from its
      shape. It is of the genus {Phaseolus} ({P. vulgaris}). See
      under {Bean}.

   {Kidney ore} (Min.), a variety of hematite or iron
      sesquioxide, occurring in compact kidney-shaped masses.

   {Kidney stone}. (Min.) See {Nephrite}, and {Jade}.

   {Kidney vetch} (Bot.), a leguminous herb of Europe and Asia
      ({Anthyllis vulneraria}), with cloverlike heads of red or
      yellow flowers, once used as a remedy for renal disorders,
      and also to stop the flow of blood from wounds;
      lady's-fingers.

Source : WordNet®

kidney stone
     n : a calculus formed in the kidney [syn: {urinary calculus}, {nephrolith},
          {renal calculus}]