verb
1.
to impair in vigor, force, activity, or sensation
the news deadened his distress
Synonyms: benumb, blunt, desensitize, dull, mull, numb
Related Word: anesthetize, paralyze, unnerve; stun, stupefy
Contrasted words: animate, vivify; energize, invigorate; activate, vitalize
Antonyms: enliven
2.
Synonyms: muffle 2, dampen, mute, stifle