Definitions of deaden:

• verb:   lessen the momentum or velocity of

  Example: "Deaden a ship's headway"

• verb:   make vapid or deprive of spirit

  Example: "Deadened wine"

• verb:   convert (metallic mercury) into a grey powder consisting of minute globules, as by shaking with chalk or fatty oil
• verb:   make less lively, intense, or vigorous; impair in vigor, force, activity, or sensation

  Example: "Deaden a sound"

• verb:   become lifeless, less lively, intense, or active; lose life, force, or vigor
• verb:   make vague or obscure or make (an image) less visible
• verb:   cut a girdle around so as to kill by interrupting the circulation of water and nutrients