What does "grind" mean?

Grind: 2. To wear down, polish, or sharpen, by friction; to make smooth, sharp, or pointed; to whet, as a knife or drill; to rub against one another, as teeth, etc.

Additional senses

  1. 2.To oppress by severe exactions; to harass. To grind the subject or defraud the prince. Dryden.
  2. 3.To study hard for examination. [College Slang]
  3. 4.To perform the operation of grinding something; to turn the millstones. Send thee Into the common prison, there to grind. Milton.
  4. 5.To become ground or pulverized by friction; as, this corn grinds well.
  5. 6.To become polished or sharpened by friction; as, glass grinds smooth; steel grinds to a sharp edge.
  6. 7.To move with much difficulty or friction; to grate.
  7. 8.To perform hard aud distasteful service; to drudge; to study hard, as for an examination. Farrar.
  8. 9.The act of reducing to powder, or of sharpening, by friction.
  9. 10.Any severe continuous work or occupation; esp., hard and uninteresting study. [Colloq.] T. Hughes.
  10. 11.A hard student; a dig. [College Slang]

Sources