ma'am

n. madam, respectful title used when addressing a woman; respectful title used when addressing a queen or a royal princess (British)

Madam or ma'am is a title for a woman. It is derived from the French madame, the equivalent of Mrs. or Ms., and literally signifying "my lady." The plural of madam in this sense is mesdames. The French madame is in turn derived from the ancient Latin mea domina meaning honored mistress of the home (domus)
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Noun
1. a woman of refinement; "a chauffeur opened the door of the limousine for the grand lady"
(synonym) dame, madam, lady, gentlewoman
(hypernym) woman, adult female
(hyponym) grande dame

(n.)
Madam; my lady; -- a colloquial contraction of madam often used in direct address, and sometimes as an appellation.
  

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