au·then·ti·cate 
/əˈθɛntɪˌkeɪt/ verb
au·then·ti·cates; au·then·ti·cat·ed; au·then·ti·cat·ing /əˈθɛntɪˌkeɪt/ verb [+ obj] : to prove that something is real, true, or genuine : to prove that something is authentic
▪ Experts authenticated the painting. ▪ The signature has been authenticated.
▪ Experts authenticated the painting. ▪ The signature has been authenticated.
— au·then·ti·ca·tion /əˌθɛntɪˈkeɪʃən/ noun [noncount]
▪ authentication of the documents
/əˌθɛntɪˈkeɪʃən/ noun [noncount] ▪ authentication of the documents
