'Head' in the Bible

"Yes, and what are you to me, Tyre, and Sidon, and all the regions of Philistia? Will you repay me? And if you repay me, I will swiftly and speedily return your repayment on your own head.

Behold, I will stir them up out of the place where you have sold them, and will return your repayment on your own head;