GRINDSTONE
grindstone
(noun) a revolving stone shaped like a disk; used to grind or sharpen or polish edge tools
Source: WordNet® 3.1
Etymology
Noun
grindstone (plural grindstones)
An abrasive wheel for sharpening, polishing or grinding.
Synonyms
• millstone
Anagrams
• Edringtons, Redingtons, stringendo
Source: Wiktionary
Grind"stone`, n.
Definition: A flat, circular stone, revolving on an axle, for grinding or
sharpening tools, or shaping or smoothing objects. To hold, pat, or
bring one's nose to the grindstone, to oppress one; to keep one in a
condition of servitude.
They might be ashamed, for lack of courage, to suffer the
Lacedæmonians to hold their noses to the grindstone. Sir T. North.
Source: Webster’s Unabridged Dictionary 1913 Edition