- a respectful or formal term of address used to a man: No, sir.
- the distinctive title of a knight or baronet: Sir Walter Scott.
- a title of respect for some notable personage of ancient times: Sir Pandarus of Troy.
- a lord or gentleman: noble sirs and ladies.
- an ironic or humorous title of respect: sir critic.
- a title of respect used before a noun to designate profession, rank, etc.: sir priest; sir clerk.
- a formal or polite term of address for a man
- a gentleman of high social status
- a title of honour placed before the name of a knight or baronet
- a title placed before the name of a figure from ancient history
