Synonyms for Peace (same or very similar meaning)
WordNet sense 1 (the general security of public places):
public security
WordNet sense 2 (the absence of mental stress or anxiety):
peacefulness, repose, serenity, ataraxis, heartsease, peace of mind
WordNet sense 3 (a treaty to cease hostilities):
pacification, peace treaty
From the ODE community, based on WordNet
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