"Biometrics' is a general term used alternatively to describe a characteristic or a process. As a characteristic: 1. A measurable biological (anatomical and physiological) and behavioral characteristic that can be used for automated recognition. As a process: 2. Automated methods of recognizing an individual based on measurable biological (anatomical and physiological) and behavioral characteristics."
Biometrics Catalog: http://www.biometricscatalog.org