Ms. is defined as an abbreviated title which is used for a woman that does not specify whether or not she is married.(abbreviation)
An example of Ms. is how someone would address a wedding invitation to a single woman.
See ms in Webster's New World College Dictionary
Origin: L memoriae sacrumsacred to the memory of
☆ or Ms
See ms in American Heritage Dictionary 4
also Msnoun pl. Mses. also Mses also Mss. or Mss (mĭzˈĭz)
Origin: Blend of Miss
Origin: and Mrs.Usage Note: Many of us think of Ms. or Ms as a fairly recent invention of the women's movement, but in fact the term was first suggested as a convenience to writers of business letters by such publications as the Bulletin of the American Business Writing Association (1951) and The Simplified Letter, issued by the National Office Management Association (1952). Ms. is now widely used in both professional and social contexts. As a courtesy title Ms. serves exactly the same function that Mr. does for men, and like Mr. it may be used with a last name alone or with a full name. Furthermore, Ms. is correct regardless of a woman's marital status, thus relegating that information to the realm of private life, where many feel it belongs anyway. Some women prefer Miss or Mrs., however, and courtesy requires that their wishes be respected.
Learn more about ms