Ferrule n. : A ring or cap of metal put round a cane, tool, handle, or other similar object, to strengthen it, or prevent splitting and wearing.

Ferrule n. : A bushing for expanding the end of a flue to fasten it tightly in the tube plate, or for partly filling up its mouth.

Example:
How do I use a Ferrule and Stop Set to secure wire rope?

Taxonomy
ferrule, free encyclopedia, metal band, wire rope, metal ring, shaft, hole, cable, search, metal objects, plastic fibers, plant, free dictionary, RHOL, thimble, Picco pipe, nickel silver, corruption.

Defination from the web:
ferrule (a corruption of Latin viriola "small bracelet," under the influence of ferrum "iron. ... Most ferrules consist of a circular clamp used to hold together and attach fibers, wires or posts, generally by crimping, swaging, or otherwise ...