nose to the grindstone

Users lay on (often strapped to) a plank above the grindstone.[1] First attested 1532, from John Frith's A Mirror to know Thyself: "This Text holdeth their noses so hard to the grindstone, that it clean disfigureth their faces."

nose to the grindstone (not comparable)

1. (idiomatic) Hard at work.

   Nose to the grindstone, he was up all night.

nose to the grindstone (plural noses to the grindstone or noses to grindstones)

1. (idiomatic, after keep, put, have, hold (one's)) used for form idioms meaning "to work hard, or focus heavily on work."

   If he'd keep his nose to the grindstone a bit more, he could be a pretty good student.

• head down, bum up