- A protective sleeve in a part intended to hold an item supported by, or passing through, the part.
- A protective sleeve of metal in the wall of a chimney used to hold the end of a stovepipe or smoke pipe.
Origin & History of “thimble”
A thimble is etymologically a ‘thumb implement’. The word goes back to Old English thȳmel, a derivative of thūma ‘thumb’. In Old English (where it is recorded only once) it was used for a ‘finger-stall’. By the time it reappears in the 15th century we find it being applied to a ‘leather finger-protector used for pushing in a needle’, and it was extended to metal thimbles, introduced in the 17th century.