Definition of "sir"

sir

/ˈsɜː(ɹ)/

noun
plural sirs
1. A man of a higher rank or position.
2. A respectful term of address to a man of higher rank or position, particularly:
  Quotations
  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
  1. to a knight or other low member of the peerage.
  2. to a superior military officer.
  3. to a teacher.
3. A respectful term of address to an adult male (often older), especially if his name or proper title is unknown.
verb
third-person singular simple present sirs, present participle sirring, simple past and past participle sirred
1. To address (someone) using "sir".
  Quotations
  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)