Emery

Business / Machine Shop / Emery: A natural abrasive used for grinding or polishing. It is being largely replaced by artificial abrasives.
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Emery Pitch

Entertainment / Baseball / Emery Pitch: A pitch that is thrown after the pitcher surreptitiously shaves or cuts the ball with a foreign object. This changes the natural spherical shape of the ball, and thus alters the path of the pitch once MORE

Abrasive

Science / Chemistry / Abrasive: A very hard, brittle, heat-resistant substance that is used to grind the edges or rough surfaces of an object. boron carbide, diamond, and corundum are abrasives. MORE