Where does “ὑποτρίβω” come from?

ὑποτρίβω (Ancient Greek) comes from Ancient Greek ῠ̔πο-, from Ancient Greek ὑπό, from Proto-Indo-European upó, from Proto-Indo-European h₃ewp-.

ὑποτρίβω (Ancient Greek): to rub off, wear away; to grate

Definitions

Step	Language	Word	Meaning
1	Ancient Greek	ῠ̔πο-	under, lower; by, under; under”, “beneath
2	Ancient Greek	ὑπό
3	Proto-Indo-European	upó	under, below
4	Proto-Indo-European	h₃ewp-	—