ratline(also ratlin), / ˈrætlɪn; `rætlɪn/ n (usu pl 通常作复数) short rope fixed between the shrouds of a sailing-ship, like a rung of a ladder, and used for climbing up or down 绳梯横索（轮船支索间作梯级用的横索）.
牛津英汉双解词典