Mrs. is a commonly used English honorific for women, usually for those who are married and who do not instead use another title, such as Doctor, Professor, President, Dame, etc. . The term originated as a contraction of the honorific Mistress, which was originally applied to both married and unmarried women in the upper class. The split into Mrs. for married women and Miss for unmarried began during the 17th century, but was not reliable until well into the 19th century. In direct address, a woman with the title Mrs. may be addressed Mrs. .

It is worth noting that Mrs. can also be used as an abbreviation for the word "marginal rate of substitution" in economics. In economics, the marginal rate of substitution (MRS) is the amount of a good that a consumer is willing to consume compared to another good, as long as the new good is equally satisfying. MRS is used in indifference theory to analyze consumer behavior.