As nouns the difference between grindstone and knifegrinder
is that grindstone is an abrasive wheel for sharpening, polishing or grinding while knifegrinder is one whose trade is the sharpening of knives on a grindstone.
grindstone
English
Noun
(
en noun)
An abrasive wheel for sharpening, polishing or grinding.
Synonyms
* millstone
knifegrinder
English
Alternative forms
* knife-grinder
Noun
(
en noun)
One whose trade is the sharpening of knives on a grindstone.