/ ˈmædəm; NAmE / noun
1.
[ sing. ] ( formal ) used when speaking or writing to a woman in a formal or business situation :
Can I help you, madam?
Dear Madam (= used like Dear Sir in a letter)
—see also ma'am
2.
[ C ] ( informal disapproving , especially BrE ) a girl or young woman who expects other people to do what she wants :
She's a proper little madam.
3.
[ C ] a woman who is in charge of the prostitutes in a brothel
••
WORD ORIGIN
Middle English : from Old French ma dame my lady.