The Collaborative International Dictionary of English v.0.48:

Courtesy \Cour"te*sy\ (k?r"t?-s?), n.; pl. Courtesies (-s?z).
   [OE. cortaisie, corteisie, courtesie, OF. curteisie,
   cortoisie, OF. curteisie, cortoisie, F. courtoisie, fr.
   curteis, corteis. See Courteous.]
   1. Politeness; civility; urbanity; courtliness.
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            And trust thy honest-offered courtesy,
            With oft is sooner found in lowly sheds,
            With smoky rafters, than in tapestry walls
            And courts of princes, where it first was named,
            And yet is most pretended.            --Milton.
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            Pardon me, Messer Claudio, if once more
            I use the ancient courtesies of speech.
                                                  --Longfellow.
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   2. An act of civility or respect; an act of kindness or favor
      performed with politeness.
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            My lord, for your many courtesies I thank you.
                                                  --Shak.
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   3. Favor or indulgence, as distinguished from right; as, a
      title given one by courtesy.
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   Courtesy title, a title assumed by a person, or popularly
      conceded to him, to which he has no valid claim; as, the
      courtesy title of Lord prefixed to the names of the
      younger sons of noblemen.

   Syn: Politeness; urbanity; civility; complaisance;
        affability; courteousness; elegance; refinement;
        courtliness; good breeding. See Politeness.
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