a title of a mayor of what is usually a major city in the United Kingdom or Commonwealth realm, with special recognition bestowed by the sovereign. However, the title or an equivalent is present in countries outside such realms, including forms such as "high mayor".
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The style of address for the office of the Lord Mayors of Belfast, Cardiff, the City of London, and York is The Right Honourable. All other Lord Mayors are The Right Worshipful. This refers only to the post, rather than the person. The title Sir can be used for salutations when the lord mayor/mayor is being addressed.
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The magistracy of Edinburgh is changed every year by election, and seems to be very well adapted both for state and authority.—The lord provost is equal in dignity to the lord mayor of London; and the four bailies are equivalent to the rank of aldermen.
Tobias Smollett. The Expedition of Humphry Clinker (1771)
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It was a nice little dinner,—seemed to me then a very Lord Mayor's Feast,—and it acquired additional relish from being eaten under those independent circumstances, with no old people by, and with London all around us.
Charles Dickens. Great Expectations (1861)
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May 7.—A big red-letter day; viz., the Lord Mayor’s reception. The whole house upset. I had to get dressed at half-past six, as Carrie wanted the room to herself.
George and Weedon Grossmith. The Diary of a Nobody (1882)
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There would be mention of the bishops in their lawn sleeves, the judges in their ermine robes, the pillory, the stocks, the treadmill, the cat o’ nine tails, the Lord Mayor’s Banquet and the practice of kissing the Pope’s toe.