Token - In authentication systems, some type of physical device (such as a card with a magnetic strip or a smart card) that must be in the individual's possession in order to gain access. The token itself is not sufficient; the user must also be able to supply something memorized, such as a personal identification number (PIN).
NIST IR 7298
NIST SP 800-63v1.0.2
NSA IATF 3-1
Token - A token is an object that represents something else, such as another object (either physical or virtual). A security token is a physical device, such as a special smart card, that together with something that a user knows, such as a PIN, will enable authorized access to a computer system or network.