A variant or intensive form of accredit; to officially certify or authorize with full credentials.
From the same Latin root as 'accredit' (credere, to believe), the '-ate' suffix creates a verb form emphasizing the action of credential-granting with greater formality, emerging in specialized institutional language.
This word is so rare that most dictionaries don't list it separately, but it shows how English speakers sometimes create intensified versions of existing words by adding '-ate'—though sometimes these extra variations fade away.
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