Synonyms for Certification (same or very similar meaning)
WordNet sense 1 (confirmation that some fact or statement is true):
corroboration, documentation
WordNet sense 2 (a document attesting to the truth of certain stated facts):
certificate, credential, credentials, certificate
WordNet sense 3 (the act of certifying or bestowing a franchise on):
enfranchisement
WordNet sense 4 (validating the authenticity of something or someone):
authentication
From the ODE community, based on WordNet
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