Grinding
来自Big Physics
Old English grindan, probably of Germanic origin. Although no cognates are known, it may be distantly related to Latin frendere ‘rub away, gnash’.
wiktionary
From Middle English gryndynge, equivalent to grind + -ing.
etymonline
grinding (adj.)
Old English, present-participle adjective from grind (v.). Meaning "oppressive, burdensome" is from 1580s. The verbal noun is from mid-14c.
