Sir n.
  1. A man of social authority and dignity; a lord; a master; a gentleman; -- in this sense usually spelled sire. [Obs.]
     He was crowned lord and sire.   --Gower.
     In the election of a sir so rare.   --Shak.
  2. A title prefixed to the Christian name of a knight or a baronet.
     Sir Horace Vere, his brother, was the principal in the active part.   --Bacon.
  3. An English rendering of the LAtin Dominus, the academical title of a bachelor of arts; -- formerly colloquially, and sometimes contemptuously, applied to the clergy.
     Instead of a faithful and painful teacher, they hire a Sir John, which hath better skill in playing at tables, or in keeping of a garden, than in God's word.   --Latimer.
  4. A respectful title, used in addressing a man, without being prefixed to his name; -- used especially in speaking to elders or superiors; sometimes, also, used in the way of emphatic formality. “What's that to you, sir?”
  Note: ☞ Anciently, this title, was often used when a person was addressed as a man holding a certain office, or following a certain business. “Sir man of law.” “Sir parish priest.”
  Sir reverance. See under Reverence, n.
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