To remove military forces, weapons, and military control from an area, usually through international agreement.
British English spelling from French demi- (to remove) plus military. The term became standard in diplomatic language during the 19th and 20th centuries for peace treaties.
When countries sign treaties to demilitarise a region, they're essentially agreeing to turn swords into ploughshares—though enforcement has proven tricky, as many demilitarised zones still bristle with heavily-armed troops watching each other.
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