Authenticate and Affirm

Authenticate

Authenticate verb - To declare (something) to be true or genuine.
Usage example: a jeweler authenticated the diamond as real

Affirm is a synonym for authenticate. In some cases you can use "Affirm" instead a verb "Authenticate".

Affirm

Affirm verb - To state as a fact usually forcefully.

Authenticate is a synonym for affirm in confirm topic. Sometimes you can use "Authenticate" instead a verb "Affirm".
Cite this Source
Affirm and Authenticate. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/authenticate/affirm
Authenticate & Affirm. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/authenticate/affirm>.
Affirm or Authenticate. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/authenticate/affirm.
Google Ngram Viewer shows how "authenticate" and "affirm" have occurred on timeline