1. whetstone; grindstone
Wikipedia definition
2. Sharpening stoneSharpening stones, water stones or whetstones are used to grind and hone the edges of steel tools and implements. Examples of items that may be sharpened with a sharpening stone include scissors, scythes, knives, razors and tools such as chisels, hand scrapers and plane blades. Though it is sometimes mistaken as a reference to the water often used to lubricate such stones, the word "whetstone" is a compound word formed with the word "whet," which means to sharpen a blade, not the word "wet".
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