keep nose to the grindstone

Related to keep nose to the grindstone: keep one's nose clean

keep (one's) nose to the grindstone

To work hard and/or diligently on something. I'm so impressed by your grades, honey—you really kept your nose to the grindstone this year, and it paid off! I've got to keep my nose to the grindstone if I'm going to get this promotion.
See also: grindstone, keep, nose
Farlex Dictionary of Idioms.

keep one's nose to the grindstone

Fig. to work hard and constantly. Son: I'll never get good grades. I might as well not even study. Mother: Don't give up yet. I'm sure that if you just keep your nose to the grindstone, you'll get the results you want. Mary kept her nose to the grindstone while her friends were out enjoying themselves.
See also: grindstone, keep, nose
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

nose to the grindstone, have/keep one's

To work hard all the time. The image, transferred from tools that must continuously be sharpened, is a vivid one and has been used since the sixteenth century. “This Text holdeth their noses to hard to the grindstone, that it clean disfigureth their faces,” wrote John Faith (A Mirrour to Knowe Thyselfe, 1539).
See also: have, keep, nose
The Dictionary of Clichés by Christine Ammer
See also:
  • keep (one's) nose to the grindstone
  • keep your nose to the grindstone
  • nose to the grindstone, keep one's
  • have (one's) nose to the grindstone
  • grindstone
  • put (one's) nose to the grindstone
  • put nose to the grindstone
  • nose to the grindstone
  • hard at (something)
  • hard at it