A variant or alternate spelling of 'détente,' meaning a relaxation of tension or hostility between nations or parties.
From French 'détente' (relaxation), from Old French 'détendre' (to relax), from Latin 'dis-' (un-) and 'tendere' (to stretch). The spelling 'dtente' appears to be a non-standard or phonetic variation of the accepted 'détente.'
The word détente became famous during the Cold War as a hopeful term, but the accent mark often gets dropped in English, sometimes appearing as 'dtente'—showing how French loanwords gradually lose their French spelling as they're adopted into English.
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