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 priest
b
: a man of rank or position
2a
—used as a usually respectful form of address
b
capitalized
—used as a conventional form of address in the salutation of a letter
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Merriam-Webster unabridged
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Time Traveler for sir
The first known use of sir was in the 13th century
See more words from the same century