authenticate
verb [ T ]
uk/ɔːˈθentɪkeɪt/ us/ɑːˈθenṱɪ-/to prove that something is real, true, or what people say it is:
Each of these signatures must be authenticated by a lawyer.
Holograms can be used to authenticate documents.
IT
to prove that someone is a particular person:
A password is used to authenticate a user.
We offer electronic certificates that authenticate the identity of internet traders.
authentication
noun [ U ] uk/ɔːˌθentɪˈkeɪʃən/ us/ɑːˌθenṱɪ-/
We needed to identify a data source that we could use for authentication.