Relating to or having the nature of a decree or decrees; pertaining to the authority to make official declarations.
From Latin decretum (decree) + -orial (relating to). The -orial suffix creates an adjective suggesting authority and jurisdiction, similar to how 'senatorial' relates to senators.
Decretorial sounds grand and archaic because it was mainly used in formal legal and religious contexts—a decretorial power is one granted by sacred or official pronouncement.
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