Authenticator

An authenticator is a way to prove to a computer system that you really are who you are (called authentication). It is either: Authenticator tokens are common when one program needs to authenticate itself to a larger server or cloud repeatedly. For instance, you (the human) might sign on to a secure website with your name and password, after which...
Found on http://en.wikipedia.org/wiki/Authenticator

authenticator

noun one who determines authenticity (as of works of art) or who guarantees validity
Found on https://www.encyclo.co.uk/local/20974
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