n. Abbr. Mdm.
1. pl. Mes·dames (mā-dăm, -däm) Used formerly as a courtesy title before a woman's given name but now used only before a surname or title indicating rank or office: Madam Ambassador.
2. Used as a salutation in a letter: Dear Madam or Sir.
3. madam Used as a form of polite address for a woman: Right this way, madam.
4. madam The mistress of a household.
5. madam A woman who manages a brothel.
[Middle English madame, from Old French ma dame; see MADAME.]
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