(mountaineering) a descent of a vertical cliff or wall made by using a doubled rope that is fixed to a higher point and wrapped around the body
source: WordNet 3.0
The beat of the drum to call soldiers to arms.
source: Webster 1913
verb
lower oneself with a rope coiled around the body from a mountainside
The ascent was easy--roping down the mountain would be much more difficult and dangerous. You have to learn how to abseil when you want to do technical climbing.