Source : Webster's Revised Unabridged Dictionary (1913)

Tolerance \Tol"er*ance\, n.
   1. (Forestry) Capability of growth in more or less shade.

   2. Allowed amount of variation from the standard or from
      exact conformity to the specified dimensions, weight,
      etc., as in various mechanical operations; specif.:
      (Coinage) The amount which coins, either singly or in
      lots, are legally allowed to vary above or below the
      standard of weight or fineness.

Tolerance \Tol"er*ance\, n. [L. tolerantia: cf. F.
   tol['e]rance.]
   1. The power or capacity of enduring; the act of enduring;
      endurance.

            Diogenes, one frosty morning, came into the market
            place, shaking, to show his tolerance. --Bacon.

   2. The endurance of the presence or actions of objectionable
      persons, or of the expression of offensive opinions;
      toleration.

   3. (Med.) The power possessed or acquired by some persons of
      bearing doses of medicine which in ordinary cases would
      prove injurious or fatal.

   {Tolerance of the mint}. (Coinage) Same as {Remedy of the
      mint}. See under {Remedy}.

Source : WordNet®

tolerance
     n 1: the power or capacity of an organism to tolerate unfavorable
          environmental conditions
     2: a disposition to allow freedom of choice and behavior [syn:
        {permissiveness}] [ant: {unpermissiveness}]
     3: the act of tolerating something
     4: willingness to recognize and respect the beliefs or
        practices of others [ant: {intolerance}]
     5: a permissible difference; allowing some freedom to move
        within limits [syn: {allowance}, {leeway}, {margin}]