With examples from Phantom of the Opera, Battlestar Galactica, CSI, & Star Trek: TNG.
This is actually a really good question. A lot of people seem to have trouble distinguishing between madam and madame. They're only separated by a single letter...
They look alike, they sound alike, they're even spelled a lot alike. What a crazy pair! But they're cousins! Iden...
*ahem* Sorry for that random interjection of The Patty Duke Show.
Both madam and madame are used to describe women, but not as interchangeably as some may think.
Madame is primarily used as the French equivalent of "Mrs.", denoting a woman's marital status. It can also be used to denote respect to an older woman of distinction, who is of a heritage other than American or British.
"It's a pleasure to finally meet you, Madame Giry. Christine has spoken of you kindly."
Madam, on the other hand, is the word that will be used more often.
- It can be used to convey a woman's rank or authority.
"With all due respect, Madam President, go frak yourself!"
- The word madam also refers to the woman in charge of a brothel, or house of prostitution.
"Brass is bringing in Lady Heather for questioning," Sofia explained to Sara.
"He gets to question a madam?" Greg asked with a grin as he walked by. "I so want his job!"
"Lady Heather's Dominion isn't a whorehouse, Greg!" Sofia growled, smiling as Sara punched him in the arm.
- It can also be used to refer to the woman in charge of the home, like "The madam isn't currently at home." This seems a bit archaic, as most people would say "The lady of the house isn't at home." On the other hand, it could be used in place of the woman's name, particularly when said by a butler or maid.
"Will Madam require anything else before retiring?" Xelo asked, staring laciviously at Lwaxana.
In the end, if the woman you're speaking of is married and French, use madame. Otherwise, use madam.
- Difference Between Madam and Madame @ Differencebetween.com
- The use of madam and madame? @ Answers.com
- madam @ Dictionary.com
- madame @ Dictionary.com