[1] : The Collaborative International Dictionary of English v.0.48

madam \mad"am\, n.; pl. madams, or mesdames. see madame.
   1. a gentlewoman; -- an appellation or courteous form of
      address given to a lady, especially an elderly or a
      married lady; -- much used in the address, at the
      beginning of a letter, to a woman. the corresponding word
      in addressing a man is sir; often abbreviated ma'am when
      used as a term of address.
      1913 webster

   2. the woman who is in charge of a household.
      pjc

   3. the woman who is in charge of a brothel.
      pjc
see also:
madams mesdames madame sir 

[2] : WordNet (r) 2.0

madam
     n 1: a woman of refinement; "a chauffeur opened the door of the
          limousine for the grand lady" syn: dame, ma'am, lady,
           gentlewoman
     2: a woman who runs a house of prostitution syn: brothel
        keeper
see also:
dame ma'am lady gentlewoman brothel keeper 

[3] : Moby Thesaurus II by Grady Ward, 1.0

43 moby thesaurus words for "madam":
   frau, fraulein, miss, mistress, mlle, mme, mmes, abbess, bawd,
   chatelaine, dame, dona, donna, dowager, fancy man, first lady,
   gigolo, goodwife, governess, great lady, homemaker, housewife,
   lady, madame, mademoiselle, maquereau, matriarch, matron,
   mem-sahib, mesdames, mistress, mother superior, pander, panderer,
   pimp, procurer, procuress, senhora, senhorita, signora, signorina,
   vrouw, white slaver

Madam >> M Words
Madam, definition of term: Madam
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