Ms. (American English) or Ms (British English; normally , but also , or when unstressed) is an English-language honorific used with the last name or full name of a woman, intended as a default form of address for women regardless of marital status. Like Miss and Mrs., the term Ms. has its origins in the female English title once used for all women, Mistress, the feminine form of Mister and Master. It originated in the 17th century and was revived into mainstream usage in the 20th century. Its usage remains controversial in Britain, with many style guides recommending not to use it unless specifically requested to.

Historical development and revival of the term

Miss and Mrs., both derived from the then formal Mistress, like Mister did not originally indicate marital status. Ms. was another acceptable, but rarely used, abbreviation for Mistress in England in the 17th and 18th centuries. During the 19th century, however, Mrs. and Miss came to be associated almost exclusively with marital status, and Ms. was popularized as an alternative in the late 20th century.

The earliest known proposal for the modern revival of Ms. as a title appeared in The Republican of Springfield, Massachusetts, on November 10, 1901: