As a nautical term, belaying refers to making a line fast to a cleat, pin or other fixed object.

In climbing, belaying is the technique of controlling the rope so that a falling climber does not fall very far. This task is usually assigned to a belayer. (Self-belaying is possible as well, but as it is an advanced technical climbing technique, the description is beyond the scope of this article.)

The belayer usually passes the rope through a belay device which allows the rope to pass freely through the device in one direction (as the climber being belayed ascends), but allows the belayer to easily lock off the rope in the event of a fall. Alternatively, a belayer could use a knot called a munter hitch and a carabiner, which effectively provides the same function as a belay device, but has the side effect of introducing a half twist into the rope as it passes through the knot.

Historically, belaying in climbing meant simply that the belayer would take a wrap of rope around his or her waist; friction between rope and the belayer's body was used to arrest a fall. This technique, known as the hip belay, is still sometimes used by climbers needing to move quickly on low-angle terrain, but on vertical rock it is no longer used as it is less reliable and more apt to injure the belayer stopping a long fall.

The person climbing is said to be "on belay" when one of these belaying methods is being used. Belaying is a critical part of the climbing system.

By using one of these belaying methods, the belayer can hold the entire weight of the climber by using relatively little force, and can easily arrest even a long fall. By using a mixture of belaying angle and hand-grip on the rope, a climber can be lowered gently by the belayer to a point where climbing can be resumed.

climbing techniques | Ropework

Assurage | Страховка (в альпинизме) | Belaying