Synonyms:
grindstone
Meaning: a revolving stone shaped like a disk; used to grind or sharpen or polish edge tools
Usage examples
This was something like a gigantic grindstone which rolled in the groove and was large enough to cover the opening when the tomb was closed.
The Boots and the Broker were sharpening a spade-- Each working the grindstone in turn: But the Beaver went on making lace, and displayed No interest in the concern: