passport (n.)

c. 1500, passe-porte, "authorization to travel through a country," from Old French passeport "authorization to pass through a port" to enter or leave a country (15c.), from passe, imperative of passer "to pass" (see pass (v.)) + port "port" (see port (n.1)). The original sense is obsolete; the meaning "document issued by competent civil authority granting permission to the person named in it to travel in or out of a country or authenticating his right to protection while abroad" is from 1540s. In early use often indicating principally the right to leave one's country.