Mrs. (American English) or Mrs (British English; standard English pronunciation: //) is a commonly used English honorific for women, usually for those who are married and who do not instead use another title (or rank), such as Dr, Professor, President, Dame, etc. In most Commonwealth countries, a full stop (period) is usually not used with the title. In the United States and Canada a period is usually used (see Abbreviation).
Mrs originated as a contraction of the honorific Mistress, the feminine of Mister, or Master, which was originally applied to both married and unmarried women. The split into Mrs for married women and Miss for unmarried began during the 17th century; the 17th century also saw the coinage of a new unmarked option Ms with a return of this usage appearing in the 20th century.
It is rare for Mrs to be written in a non-abbreviated form, and the unabbreviated word lacks a standard spelling. In literature it may appear as missus or missis in dialogue. A variant in the works of Thomas Hardy and others is "Mis'ess", reflecting its etymology. Misses has been used but is ambiguous, as this is a commonly used plural for Miss. The plural of Mrs is from the French: Mesdames. This may be used as-is in written correspondence, or it may be abbreviated Mmes.
In medical professional circles in UK, all MDs (doctors with a medical/surgucal degree) are required (both legally and professionally) to use *his her legal name which he/she used at the time of his/her professional qualification*. A MD/Surgeon/GP is not allowed to change his/her "professional name" (under which she/he practices Medicine/Surgery) at any point in her/his professional practice. On a personal level, he/she can call herself/himself what he/she likes socially, as long as she/he only practices professionally under his/her name which was current on the date of qualification. A doctor/surgeon will be admitted to the appropriate Professional Register under one name, and there is no scope for updating the professional registers to change a profesdional's name. (Marriage, Changes of name due to Deed Poll/Statutory Declaration/Common Usage, and Divorce make no difference to this rule. If a MD qualified as Dr Dolly Poltreath, she is not allowed to Practice as Dr McBoatface if she marries B.T. McBoatface, or if she divorces A.K. Poltreath and reverts to her maiden name of Dolly McBoatface socially).
Mrs was most often used by a woman when married, in conjunction with her husband's first and last names (e.g., Mrs John Smith). A widow would also be addressed with the same title as when she was married. Mrs was rarely used before a woman's first name, her birth name, or a hyphenated surname her husband was not using. For example, Mrs Jane Smith, Mrs Miller (wife of John Smith), or Mrs Miller-Smith were considered incorrect by many etiquette writers, especially of the early 20th century.
In several languages, the title for married women such as Madame, Señora, Signora, or Frau, is the direct feminine equivalent of the title used for men; the title for unmarried women is a diminutive: Mademoiselle, Señorita, Signorina, or Fräulein. For this reason, usage had shifted toward using the married title as the default for all women in professional usage. This had long been followed in the United Kingdom for some high-ranking household staff, such as housekeepers, cooks, and nannies, who were called Mrs as a mark of respect regardless of marital status. However, in the late 20th century the marital-neutral Ms became more common for women professionally and socially.
In the United Kingdom, the traditional form for a divorcée was Mrs Jane Smith. In the U.S., the divorcée originally retained her full married name unless she remarried. Later, the form Mrs Miller Smith was sometimes used, with the birth surname in place of the first name. However, the form Mrs Jane Miller eventually became widely used for divorcées, even in formal correspondence; that is, Mrs preceded the divorcée's maiden name.
Before social mores relaxed to the point where single women with children were socially acceptable, the unwed mother was often advised by etiquette mavens like Emily Post to use Mrs with her maiden name to avoid scrutiny.
The separation of Miss and Mrs became problematic[how?] as more women entered the white-collar workforce. Women who became famous or well known in their professional circles before marriage often kept their birth names, stage names, or noms de plume. Miss became the appellation for celebrities (e.g., Miss Helen Hayes, or Miss Amelia Earhart) but this also proved problematic, as when a married woman did use her husband’s last name but was still referred to as Miss; see more at Ms and Miss.
It is now very uncommon for a woman to be addressed by her husband's first name; however, this still sometimes occurs if a couple is being addressed jointly, such as in Mr and Mrs John Smith.
Many married women still use the title with their spouse's last name but retaining their first name (e.g., Mrs Jane Smith). Other married women choose not to adopt their spouse's last name at all. It is generally considered polite to address a woman by Ms rather than Mrs, unless the preference of the woman in question is clearly known. This is especially true in written communication, as dictated by professional etiquette. 
Modern etiquette provides various options in addressing married couples in which the wife uses her own last name, or uses a title such as Dr, Mayor, or Ms. Etiquette writer Judith Martin ("Miss Manners") generally advises that, in non-standard situations, the individuals be addressed on separate lines when writing invitations (e.g., "Dr Sue Martin/Mr John Martin").
In direct address, a woman with the title Mrs may be addressed Mrs [Lastname], or with the stand-alone Madam or Ma'am, although the latter two are more often used for any adult woman, regardless of marital status, in modern conversation. It is normally considered correct to address a woman as Ms [Lastname], regardless of her marital status.
A woman who has a long-term sexual relationship with a partner who is married may be referred to as that person's "mistress".
- "Abbreviations : Capital Letters and Abbreviations". www.sussex.ac.uk. Retrieved 26 February 2018.
- Spender, Dale. Man-Made Language.
- Stannard, Una. Mrs Man.
- Post, Emily. Etiquette. 1922.
- "Guide to Addressing Correspondence - The Emily Post Institute, Inc". emilypost.com.