A chain, string, or wire connected to a [[monocle]] intended to be connected to the wearer's clothing to prevent the monocle from being able to fall to the ground and damaging it.  Despite its intended purpose to protect the monocle, they're commonly depicted dangling with a hanging ornament on the end instead.  This would, if anything, make it easier for the monocle to fall out.

h4. See also

* [[Eyewear strap]]