deaden
dead.en \'ded-*n\ \'ded-nin, -*n-in\ vb or dead.en.ing 1: to impair in vigor or sensation : BLUNT 2a: to deprive of brilliancy 2b: to make vapid or spiritless 2c: to make (as a wall) impervious to sound 3: to deprive of life : KILL : to become dead : lose life or vigor