Used as a form of polite address for a woman: Will that be cash or charge, ma'am? (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "ma'am" in a sentence
"Anyone in harness to her Majesty in one form or another learns to use the term 'ma'am' as in 'charm' or sometimes as in 'jam'."
"Although we do hear about how distressing it is to be called "ma'am" by a bartender at a "Nineties" party held by ironic hipsters."
"• The queen is referred to as "your majesty" on the first greeting; in subsequent references, she is to be called "ma'am.""