Username (noun)

A name or nickname that a person uses on a particular computer system or website, in order to identify themselves to other users.

Origin:

Late 20th century: blend of user and name.

Examples:

  1. Please enter your username and password to log in.
  2. Your username must be unique and can't be changed later.
  3. A username is a unique identifier that allows a user to access an account or system.
  4. I forgot my username, can you help me to retrieve it?
  5. Please choose a username that is easy to remember and not easily guessable.
Some random words: horsetrading, rehash, antitoxin