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Webster 1913 Edition

obs.

Ground.

Sir W. Scott.

grinded

(nonstandard) simple past tense and past participle of grind
- 2007 May 15, Ben Shpigel, “New York Welcomes Floyd Back to Town”, in New York Times:
  I just grinded it out and played hard, and these fans loved that.
(video games) simple past tense and past participle of grind
I grinded for experience before I took on the boss.