Etymology From Middle English sir, unstressed form of sire, borrowed from Old French sire (“master, sir, lord”), from Latin senior (“older, elder”), from senex (“old”). Doublet of seigneur, seignior, senhor, senior, señor, senyor, signore, and sire.
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A man of a higher rank or position.
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A respectful term of address to a man of higher rank or position, particularly
Jeeves: Foreign travel often liberates emotions best kept in check, sir. The air of North America is notoriously stimulating in this regard, as witness the regrettable behavior of its inhabitants in 1776. B. Wooster: Hm? What happened in 1776, Jeeves? Jeeves: I prefer not to dwell on it, if it's convenient to you, sir.1991 May 12, “Kidnapped!”, in Jeeves and Wooster, Series 2, Episode 5:
› A respectful term of address to a man of…
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to a knight or other low member of the peerage.
Just be careful. He gets whingy now if you don't address him as Sir John.
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to a superior military officer.
Sir, yes sir.
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to a teacher.
Here's my report, sir.
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A respectful term of address to an adult male (often older), especially if his name or proper title is unknown.
Excuse me, sir, do you know the way to the art museum?
Knowledge, sir, should be free to all!1967 November 3, I, Mudd (Star Trek) (Science Fiction), Roger C. Carmel (actor), Paramount Domestic Television:
Etymology From Middle English sir, unstressed form of sire, borrowed from Old French sire (“master, sir, lord”), from Latin senior (“older, elder”), from senex (“old”). Doublet of seigneur, seignior, senhor, senior, señor, senyor, signore, and sire.
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Informal To address another individual using "sir".
Sir, yes, sir! —Don't you sir me, private! I work for a living!
Don't "Sir" me, young man, you have no idea who you're dealing with!1997, Ed Solomon, Men in Black, spoken by Agent K (Tommy Lee Jones):
“Every minute,” continued M. Krempe with warmth, “every instant that you have wasted on those books is utterly and entirely lost. You have burdened your memory with exploded systems, and useless names. Good God! in what desert land have you lived, where no one was kind enough to inform you that these fancies, which you have so greedily imbibed, are a thousand years old, and as musty as they are ancient? I little expected in this enlightened and scientific age to find a disciple of Albertus Magnus and Paracelsus. My dear Sir, you must begin your studies entirely anew.”1816 June – 1817 April/May (date written), [Mary Shelley], chapter II, in Frankenstein; or, The Modern Prometheus. […], volume I, London: […] [Macdonald and Son] for Lackington, Hughes, Harding, Mavor, & Jones, published 1 January 1818, →OCLC, pages 69–70:
The family tree boasts an astonishing array of celebrated historical figures from the prophet Isaiah to Sir Isaiah Berlin, from Felix Mendelssohn to Karl Marx and Moses Montefiore. The list also includes Yehudi Menuhin, Helena Rubinstein, the Rothschilds and even Rosenstein himself.2004 October 24, Bill Gladstone, “The oldest family in the world”, in Jewish Telegraphic Agency:
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UK The titular prefix given to a knight or baronet.
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Philippines, Colloquial, Informal A respectful term of address or reference to a man of higher rank or position before the man's given name or nickname.