password

A secret word, phrase, or sequence of characters that must be presented in order to gain access or admittance.

A secret parole or countersign by which a friend may be distinguished from a stranger, and allowed to pass.

A word to be given before a person is allowed to pass; a watchword; a countersign.

A secret word used to gain admittance or to gain access to information; watchword.

A string of characters used to log in to a computer or network, to access a level in a video game, etc.

To protect with a password.

a secret word or phrase known only to a restricted group