Source : Webster's Revised Unabridged Dictionary (1913)

Kindness \Kind"ness\, n. [From {Kind}. a.]
   1. The state or quality of being kind, in any of its various
      senses; manifestation of kind feeling or disposition
      beneficence.

            I do fear thy nature; It is too full o' the milk of
            human kindness To catch the nearest way. --Shak.

            Unremembered acts Of kindness and of love.
                                                  --Wordsworth.

   2. A kind act; an act of good will; as, to do a great
      kindness.

   Syn: Good will; benignity; grace; tenderness; compassion;
        humanity; clemency; mildness; gentleness; goodness;
        generosity; beneficence; favor.

Source : WordNet®

kindness
     n 1: the quality of being warm-hearted and considerate and humane
          and sympathetic [ant: {unkindness}]
     2: tendency to be kind and forgiving [syn: {forgivingness}]
     3: a kind act [syn: {benignity}]