horse (someone) up

work or haze (someone) cruelly or unfairly. From the nautical term horsing up, the action of using a horsing iron to caulk the deck of a wooden vessel. A horsing iron is a broad-bladed, dull-edged chisel with a long wooden handle. It is held in position along a deck seam by one man while another man drives it in hard using a heavy wooden mallet to consolidate the oakum between the planks.