The Collaborative International Dictionary of English v.0.48:

peacetime \peacetime\ n.
   A period of time during which there is no war; as, civil
   liberties are valued more highly in peacetime than in war.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

peacetime
    n 1: a period of time during which there is no war

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "peacetime":
   accord, at peace, bloodless, calm, cessation of combat, concordant,
   exemption from hostilities, freedom from war, halcyon, harmony,
   idyllic, liberty in tranquillity, orderly, pacific, pastoral, pax,
   peace, peaceable, peaceful, piping, quiet, restful, serene, soft,
   tranquil, untroubled