Source : Webster's Revised Unabridged Dictionary (1913)

Deaden \Dead"en\, v. t.
   To render impervious to sound, as a wall or floor; to deafen.

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®

deaden
     v 1: make vague or obscure or make (an image) less visible;
          "muffle the message" [syn: {dampen}, {damp}]
     2: cut a girdle around so as to kill by interrupting the
        circulation of water and nutrients; "girdle the plant"
        [syn: {girdle}]
     3: make vapid or deprive of spirit; "deadened wine"
     4: lessen the momentum or velocity of; "deaden a ship's
        headway"
     5: become lifeless, less lively, intense, or active; lose life,
        force, or vigor
     6: make less lively, intense, or vigorous; impair in vigor,
        force, activity, or sensation; "Terror blunted her
        feelings"; "deaden a sound" [syn: {blunt}] [ant: {enliven}]
     7: convert (metallic mercury) into a grey powder consisting of
        minute globules, as by shaking with chalk or fatty oil