"grindin" is probably misspelled. Trying grinding instead Definition of grinding
grinding has definitions from the field of physics
1
[ noun ] matter resulting from the process of grinding

Examples

"vegetable grindings clogged the drain"

2
[ noun ] a harsh and strident sound (as of the grinding of gears)
3
[ noun ] (physics) the wearing down of rock particles by friction due to water or wind or ice
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