Section 2(c) in The Aadhaar (Targeted Delivery of Financial and Other Subsidies, Benefits and Services) Act, 2016
(c)"authentication" means the process by which the Aadhaar number alongwith demographic information or biometric information of an individual is submitted to the Central Identities Data Repository for its verification and such Repository verifies the correctness, or the lack thereof, on the basis of information available with it;
