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mayor of the palace

noun

one of a line of hereditary administrative lieutenants to the Merovingian kings who eventually took over royal function and title in the Frankish kingdoms; a palatine.

Origin of mayor of the palace

1520–30; translation of Medieval Latin major domūs; see major-domo
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019