What does "grinder" mean?

Grinder: One of the double teeth, used to grind or masticate the food; a molar.

Additional senses

  1. 2.(Zoöl.) The restless flycatcher (Seisura inquieta) of Australia; -- called also restless thrush and volatile thrush. It makes a noise like a scissors grinder, to which the name alludes. Grinder's asthma, phthisis, or rot (Med.), a lung disease produced by the mechanical irritation of the particles of steel and stone given off in the operation of grinding.

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