'Grind' in the Bible

What mean ye that ye beat my people to pieces, and grind the faces of the poor? saith the Lord GOD of hosts.

Bread grain is ground; for he will not be always threshing it: and though the wheel of his cart and his horses scatter it, he doth not grind it.

Take the millstones, and grind meal: uncover thy locks, make bare the leg, uncover the thigh, pass over the rivers.