Dominus (title)

Dominus is the Latin word for master or owner. As a title of sovereignty the term under the Roman Republic had all the associations of the Greek Tyrannos; refused during the early principate, it finally became an official title of the Roman Emperors under Diocletian. Dominus, the French equivalent being "sieur", was the Latin title of the feudal, superior and mesne, lords, and also an ecclesiastical and academical title. The ecclesiastical title was rendered in English "sir", which was a common prefix before the Reformation for parsons, as in Sir Hugh Evans in Shakespeare's Merry Wives of Windsor. The academical use was for a bachelor of arts, and so is still used at the University of Cambridge and other universities. The shortened form "dom" is used as a prefix of honor for ecclesiastics of the Roman Church, and especially for members of the Benedictine and other religious orders. The same form is also a title of honor in Portugal, as formerly in Brazil, used by members of the blood royal and others on whom it has been conferred by the sovereign. The Spanish form "don" is also a title, formerly applicable only to the nobility, and now one of courtesy and respect applied to any member of the better classes. The feminine form "doña" is similarly applied to a lady.
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