Source : Webster's Revised Unabridged Dictionary (1913)

Deaden \Dead"en\, v. t. [imp. & p. p. {Deadened}; p. pr. & vb.
   n. {Deadening}.] [From {Dead}; cf. AS. d?dan to kill, put to
   death. See {Dead}, a.]
   1. To make as dead; to impair in vigor, force, activity, or
      sensation; to lessen the force or acuteness of; to blunt;
      as, to deaden the natural powers or feelings; to deaden a
      sound.

Source : WordNet®

deadened
     adj 1: devoid of physical sensation; numb; "his gums were dead from
            the novocain"; "she felt no discomfort as the dentist
            drilled her deadened tooth"; "a public desensitized by
            continuous television coverage of atrocities" [syn: {dead}]
     2: made or become less intense; "the deadened pangs of hunger"