abseil
/ˈæbseɪl; `æbsel/ v[I, Ipr, Ip]
(in mountaineering) descend a steep slope or vertical rock face by using a double rope that is fixed at a higher point （在登山运动中, 使用固定於高处的双摺绳沿悬崖峭壁）缘绳下降
abseil down the mountain 从山坡上缘绳下降. abseil, n act of abseiling 缘绳下降.