Secret word is a term that refers to a confidential, not widely known, or shared word used as an authentication factor for security purposes. There are several synonyms available to describe a secret word, and some of them include passphrase, password, security code, access code, PIN, and passcode. Passphrase can be defined as a longer phrase that is used as a password. Password is commonly used to describe a word or combination of characters used as a key to access a system or device. Security code is a string of numbers, letters, or symbols used to authenticate access to a secure system. Access code refers to a unique combination that allows access to a specific location or device. PIN and passcode both refer to a numeric sequence used for authentication purposes.