Other forms: rappelling; rappelled; rappeling
When rock climbers rappel, they lower themselves down the side of a wall or mountain. To rappel safely, a climber uses special anchors and climbing ropes, as well as the help of another person.
Descending is the riskiest part of mountaineering, so many climbers rappel instead of simply climbing down using hand- and footholds. Various tools and equipment can help a climber rappel even more safely, but the most important one is a good rope that's securely anchored. The French rappel literally means "recall." Some English speakers use the term abseil instead.