ratline (also ratlin)

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）.

rather than, rather too, ratification, ratify, rating, ratio, ratiocination, ration, rational, rationale, rationalism, rationalist, rationalistic, rationality, rationalization, rationalization, rationalisation, rationalize, rationalize, rationalise, rationally, rationing, rats, rattan, ratter, rattle, rattlesnake, rattling, ratty, raucous, raucously, raucousness, raunchily, raunchiness, raunchy, ravage, rave, ravel, raven, ravening, ravenous, ravenously,