patent [LME] The word patent comes via Old French from the Latin patens ‘lying open’ from the verb patere ‘to be open’. In early use it was found in the phrase letters patent, an open document issued by a monarch to record a contract or confer a privilege. It also meant more generally ‘open to view’. Use of the word to denote a licence to manufacture a commodity dates from the late 17th century. The shiny-surfaced material [E20th] is a shortening of patent leather [L18th].