deaden

verb

1. make vague or obscure or make (an image) less visible"muffle the message"
2. cut a girdle around so as to kill by interrupting the circulation of water and nutrients"girdle the plant"
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"
7. convert (metallic mercury) into a grey powder consisting of minute globules, as by shaking with chalk or fatty oil