A defile crossing the Greenway between the Barrow-downs and the South Downs, translated by Christopher Tolkien as “long climb” (UT/278, 348). This name is a combination of and “long” and rath “(climbing) street”.
Conceptual Development: This location first appeared in Lord of the Rings drafts with the name N. Amrath (perhaps “?up-course”), soon changed to Andrath (TI/72, 79). It also appeared on draft maps for the Lord of the Rings (TI/298, 305), but the name did not appear in the published book or its maps. The location was mentioned again in Tolkien’s private essays on “The Hunt for the Ring” (UT/348). In a different essay on “The Disaster at Gladden Fields”, the name Andrath was applied to the “high-climbing pass” over the Misty Mountains, the pass that Bilbo and the Dwarves used in the Hobbit, more fully Cirith Forn en Andrath (UT/271, 278 note #4).
and (“long”) + rath (“course, passage”)