SG Heritage Dictionary

Ferrule [Noun] Webster's Dictionary 1828

A ring of metal put round a cane or other thing to strengthen it.

Ferrule [Noun] Webster's Dictionary 1913

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

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