truce
/truːs/
noun
An agreement between enemies or opponents to stop fighting or arguing for a certain time.
Origin
Middle English trewes, trues (plural), from Old English trēowa, plural of trēow ‘belief, trust’, of Germanic origin; related to Dutch trouw and German Treue, also to true.
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In a trice they agreed to terms of the truce. The single punch each had taken to the cheek convinced each of them that cooperation was less painful than fighting.