grindstone

US [ˈɡraɪndˌstoʊn]
UK [ˈɡraɪndˌstəʊn]
  • n.磨石;砂轮
  • Web磨刀石;旋转磨石;磨刀椅
Plural Form:grindstones  
grindstone
n.
1.
磨石;砂轮a round stone that is turned like a wheel and is used to make knives and other tools sharp