letters patent: Meaning and Definition of

let'ters pat'ent

Pronunciation: [key]
— Law. Law.
  1. a written or printed instrument issued by a sovereign power, conferring upon a patentee some right, as the exclusive right to land or the exclusive right to make, use, and sell an invention for a limited time.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.