sir

noun

1. A man of a higher rank or position.
2. 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.”

3. A respectful term of address to a man of higher rank or position

   “Just be careful. He gets whingy now if you don't address him as Sir John.”

4. A respectful term of address to a man of higher rank or position

   “Sir, yes sir.”

5. A respectful term of address to a man of higher rank or position

   “Here's my report, sir.”

6. 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!”

7. (alt-of)Alternative letter-case form of sir.

   “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.”

8. (British)The titular prefix given to a knight or baronet.
9. (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.
10. (abbreviation, alt-of, countable, initialism, uncountable)Initialism of surface insulation resistance.
11. (abbreviation, alt-of, countable, uncountable)Abbreviation of silent information regulator.

verb

1. (informal, transitive)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!”

name

1. (alt-of, alternative)Alternative form of Syr.

   “The Kara-tau, or "Black Mountain," the last spur of the Tian-shan towards the north-west, seldom exceeds 6,500 feet in height, but is geographically of great importance, as forming the water-parting between the Sir and Chu basins. It also abounds most in coal, iron, copper, and argentiferous lead.”

2. (abbreviation, alt-of, initialism)Initialism of Special Intensive Revision, a voter-roll revision process in India.

adj

1. (abbreviation, alt-of, initialism, not-comparable)Initialism of susceptible-infected/infectious-removed/recovered.