1. Caused to hear poorly or not at all
   "The mother learned how to read lips to help her deafened son"

1. Make or render deaf
   "The explosion deafened several workers"
    
2. Be unbearably loud
   "a deafening noise"
    
3. Make soundproof
   "deafen a room"

See also: deaf

Type of: break, damp, dampen, desensitise [Brit], desensitize, go, soften, sound, weaken