Definition of "grind"

grind¹

/ˈɡɹaɪnd/

verb
third-person singular simple present grinds, present participle grinding, simple past and past participle ground or grinded
1. (transitive) To reduce to smaller pieces by crushing with lateral motion.
2. (transitive) To shape with the force of friction.
3. (metalworking) To remove material by rubbing with an abrasive surface.
4. (intransitive) To become ground, pulverized, or polished by friction.
5. To move with much difficulty or friction; to grate.
6. (sports, intransitive) To slide the flat portion of a skateboard or snowboard across an obstacle such as a railing.
7. (transitive) To oppress, hold down or weaken.
8. (slang, intransitive) To rotate the hips erotically.
  Quotations
  She said, "How'd you like to waste some time?" / And I could not resist when I saw little Nikki grind
  1984, Prince (lyrics and music), “Darling Nikki”, in Purple Rain, performed by Prince and the Revolution
9. (slang) To dance in a sexually suggestive way with both partners in very close proximity, often pressed against each other.
10. (video games) To repeat a task a large number of times in a row to achieve a specific goal.
  Quotations
  Similarly, nearly all massively multiplayer online role-playing games (MMORPGs), such as Dungeons & Dragons Online, feature grind: Players repeat tasks, or often “quests”, to gain in-game currency to spend on weapons or other ancillary items.
  2013, Will Luton, Free-to-Play: Making Money From Games You Give Away, New Riders, page 38
  To extend the variety past that, you'll need to unlock new units in each class, meaning you have to grind through the rather lengthy process of using every one of your class’ weapons and skills significantly across several matches.
  2015 February 14, Steven Strom, “Evolve Review: Middle of the food chain”, in Ars Technica‎
11. (transitive) To operate by turning a crank.
12. To produce mechanically and repetitively as if by turning a crank.
13. (computing, dated) To automatically format and indent code.
14. To instill through repetitive teaching.
15. (slang, Hawaii) To eat.
16. (intransitive, slang) To work or study hard; to hustle or drudge.
  Quotations
  One evening, during evening work, Charlie was trying hard to do the verses which had been set to his form. […] Wilton, whose conduct had been more impertinent than that of any one else, said to Charlie— “I say, young Evson, how you are grinding.” “I have these verses to do,” said Charlie simply.
  1862, Frederic W. Farrar, St. Winifred's: or the World of School
17. (transitive, slang) To annoy or irritate (a person); to grind one's gears.
  Quotations
  I need to pontificate on something that really grinds me. So here goes. I am sick and tired of lazy thinkers using the defense of “legislated morality.”
  2003, Steven Wunderink, Minding Your Spiritual Business: Life Stories with Life Sense, page 139
noun
countable and uncountable, plural grinds
1. The act of reducing to powder, or of sharpening, by friction.
2. Something that has been reduced to powder, something that has been ground.
3. A specific degree of pulverization of coffee beans.
4. A tedious and laborious task.
  Quotations
  Running again in more open agricultural country, the Harrogate line encounters a short downgrade before the stiff uphill grind to Harrogate begins.
  1961 February, D. Bertram, “The lines to Wetherby and their traffic”, in Trains Illustrated, page 101
5. A grinding trick on a skateboard or snowboard.
6. (archaic, slang) One who studies hard.
  Quotations
  If you are at all bright, don't be a grind. Grinding may make a second-hand genius of you (for all the real things are dead), and if you become a genius you will be sure to smoke dope or swallow laudanum. They all did it.
  1900, “Gifford Arthur Nelson”, in The Naughty-Naughtian, page 118
  […] I suppose I don't know much about books, compared with you—”“Oh, I was never much of a grind,” the other cut in hastily.
  1911, Sunset, volume 27, page 440
7. (uncountable, music) Clipping of grindcore (“subgenre of heavy metal”).
8. (slang) Hustle; hard work.

grind²

/ˈɡɹɪnd/

noun
plural grinds
1. A traditional communal pilot whale hunt in the Faroe Islands.