Biometric

A physical or behavioral characteristic of a human being.

Any specific and uniquely identifiable physical human characteristic, e.g., of the retina, iris, acoustic spectrum of the voice (i.e., voiceprint), fingerprint(s), handwriting, pattern of finger lengths, etc., that may be used to validate the identity of an individual. Note: Biometrics provide a highly secure means of identification, for purposes of security involving, e.g., Internet communications and cryptosystems.