Of or belonging to a plenipotentiary; possessing or conferring full power or authority.
Mid 17th century; earliest use found in Guy Miege (bap. 1644, d. ?1718), author and lexicographer. From post-classical Latin plenipotent-, plenipotens plenipotent + -ial, probably after potential. Slightly earlier currency is probably implied by plenipotentiality.
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