meaning of seigniorage
1. Something claimed or taken by virtue of sovereign prerogative; specifically, a charge or toll deducted from bullion brought to a mint to be coined; the difference between the cost of a mass of bullion and the value as money of the pieces coined from it.
2. A share of the receipts of a business taken in payment for the use of a right, as a copyright or a patent.
3. charged by a government for coining bullion