Source : Webster's Revised Unabridged Dictionary (1913)

Softening \Sof"ten*ing\,
   a. & n. from {Soften}, v.

   {Softening of the brain}, or {Cerebral softening} (Med.), a
      localized softening of the brain substance, due to
      hemorrhage or inflammation. Three varieties, distinguished
      by their color and representing different stages of the
      morbid process, are known respectively as red, yellow, and
      white, softening.

Soften \Sof"ten\, v. t. [imp. & p. p. {Softened}; p. pr. & vb.
   n. {Softening}.]
   To make soft or more soft. Specifically:
   (a) To render less hard; -- said of matter.

             Their arrow's point they soften in the flame.
                                                  --Gay.
   (b) To mollify; to make less fierce or intractable.

             Diffidence conciliates the proud, and softens the
             severe.                              --Rambler.
   (c) To palliate; to represent as less enormous; as, to soften
       a fault.
   (d) To compose; to mitigate; to assuage.

             Music can soften pain to ease.       --Pope.
   (e) To make calm and placid.

             All that cheers or softens life.     --Pope.
   (f) To make less harsh, less rude, less offensive, or less
       violent, or to render of an opposite quality.

             He bore his great commision in his look, But
             tempered awe, and softened all he spoke. --Dryden.
   (g) To make less glaring; to tone down; as, to soften the
       coloring of a picture.
   (h) To make tender; to make effeminate; to enervate; as,
       troops softened by luxury.

Source : WordNet®

softening
     adj : having a softening or soothing effect especially to the skin
           [syn: {demulcent}, {emollient}, {salving}]
     n : the process of becoming softer; "refrigeration delayed the
         softening of the fruit"; "he observed the softening of
         iron by heat"