term:

Royalty

royalty n

pl: -ties
1 : a right delegated (as to an individual or corporation) by a sovereign
2 a : a share of the profit or product reserved by the grantor esp. of an oil or mineral lease compare overriding royalty
b : a payment made to an author or composer for each copy of a work sold or to an inventor for each article sold under a patent

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.