Etymology

Pre-19th century contraction of "Mistress" (http://www.buffalonews.com/opinion/columns/missmanners/index.html); widely adopted by feminists from the 1970s onwards as a non-sexist title that does not reveal or assume the marital status of the woman to which it is applied, by analogy with Mr, which functions in this way.

Noun

1. A title used before an adult female's name or surname instead of Miss or Mrs.

   Ms. Jane Doe

   Ms. Doe

Usage notes

Usually written Ms. with a period in North America, and Ms, without, in Britain. See the notes in the Wikipedia article