passport
/ˈpɑːspɔːt/noun
1- an official document issued by a government, certifying the holder's identity and citizenship and entitling them to travel under its protection to and from foreign countries护照。
1.1
- in sing. a thing that ensures admission to or the achievement of something保障, 手段：
good qualifications are a passport to success.
良好的资质是成功的保障。
词源
late 15th cent. (denoting authorization to depart from a port)： from French passeport, from passer 'to pass' + port 'seaport'.