dampen

verb

1. suppress or constrain so as to lessen in intensity"Stifle your curiosity"
2. make moist"The dew moistened the meadows"
3. deaden (a sound or noise), especially by wrapping
4. reduce the amplitude (of oscillations or waves)
5. make vague or obscure or make (an image) less visible"muffle the message"
6. check; keep in check (a fire)
7. lessen in force or effect"soften a shock"