Definition of sir
1a : a man entitled to be addressed as sir —used as a title before the given name of a knight or baronet and formerly sometimes before the given name of a priestb : a man of rank or position
2a —used as a usually respectful form of addressb capitalized —used as a conventional form of address in the salutation of a letter
Recent Examples of sir from the Web
On one of these plays, J. R. Smith stepped out of the way, as if to say, go right ahead, sir, enjoy yourself.
It’s also possible SIR-Spheres may help patients with a form of cancer that starts in the bile duct, for whom there is a dearth of effective treatments, said UBS’s Goodsall, who rates Sirtex a buy.
Senator Bob Corker, Republican from Tennessee, thanks for coming on, sharing your views, sir.
Mayor Landrieu, welcome back to Meet the Press, sir.
Who would have predicted, for example, that a Broadway musical that 99 percent of the population hasn’t even been able to see (Hamilton) would cause such a worldwide stir, sir?
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sir'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of sir
Middle English, from sire
First Known Use: 13th centurySee Words from the same year
SIR Defined for English Language Learners
Definition of sir for English Language Learners
—used without a name as a form of polite address to a man of rank or authority (such as a military or police officer, teacher, or master)
Sir —used without a name as a form of address at the beginning of a formal letter
Sir —used as a title before the name of a knight or baronet
SIR Defined for Kids
Definition of sir for Students
1 —used without a name as a form of polite address to a man May I help you, sir?
2 cap —used as a title before the given name of a knight or a baronet Sir Walter Raleigh
3 cap —used without a name as a form of address at the beginning of a letter
Seen and Heard
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