tranquillity

tranquillity (http://definr.com/tranquillity)

     n 1: an untroubled state; free from disturbances [syn: quiet]
     2: a state of peace and quiet [syn: tranquility, quietness,
         quietude]
     3: a disposition free from stress or emotion [syn: repose, quiet,
         placidity, serenity, tranquility]