Stopper Knot

A knot formed in a line to prevent its end or another part from passing through a fitting or opening.

Common examples include the figure-of-eight, double overhand and Ashley stopper, chosen according to rope construction, required bulk and ease of untying. A stopper knot may also provide a temporary handhold or mark, but those are secondary uses.

The knot must be larger than the opening under load and leave adequate tail. Some modern slippery or high-modulus lines require a larger or specifically tested stopper, and an end knot is not a substitute for a properly secured bitter end where complete run-out would be dangerous.