belay slave
n.— «The technical term for the climber who goes first is the “leader”; that’s the climber on the “sharp” end of the rope—the end you can hurt yourself on. The term for the climber who holds the rope and follows the route is “belay slave.”» —“A Match Made in Canada” by Michael J. Ybarra Wall Street Journal Nov. 12, 2008. (source: Double-Tongued Dictionary)