Patent

letters patent. A grant of some privilege, property or authority, made by the state or sovereign to one or more individuals; a grant by the state of the exclusive' privilege of making, using and vending, and authorizing others to make, use and vend, an invention; a grant by government of public lands. Patent right: a right granted or conferred by a patent.

In English law

Patent rolls: rolls containing the records of letters patent granted by the crown since the year 1516.