WordWeb Online

1. Not disturbed by strife, turmoil or war
   "peaceful times"; "a far from peaceful Christmas"; "peaceful sleep"; "a peaceful nation";
   - peaceable
    
2. Free of noise and disturbance, with little activity
   "a peaceful scene by the river";
   - calm, tranquil, serene
    
3. Peacefully resistant in response to injustice
   "peaceful resistance";
   - passive

See also: amicable, dovish, eirenic, halcyon, irenic, nonaggressive, nonbelligerent, nonviolent, pacific, pacifist, pacifistic, peaceable, peace-loving, quiet, unaggressive

Antonym: unpeaceful

Encyclopedia: Peaceful, the World Lays Me Down