cantilever
noun [ C ] engineering specialized uk/ˈkæn.tə.liː.vər/ us/ˈkæn.t̬ə.liː.vɚ/
（支撑桥梁等的）悬臂梁，肱梁
a long bar that is fixed at only one end to a vertical support and is used to hold a structure such as an arch, bridge, or shelf in position
a cantilever bridge 悬臂桥