razor wire
noun [ U ] uk/ˈreɪ.zə ˌwaɪər/ us/ˈreɪ.zɚ ˌwaɪr/
（设于高墙上防止翻越的）尖利铁丝网，刺钢丝
wire with pieces of sharp metal fixed across it, often positioned on top of walls, such as those surrounding a prison, to stop people climbing over the walls