Kept woman

A mistress is a relatively long-term female lover and companion who is not married to her partner, especially when her partner is himself married.

Generally, the relationship is stable and at least semi-permanent, but the couple does not live together openly and the relationship is usually, but not always, secret. There is often also the implication (if not the fact) that the mistress is "kept" – i.e. that her lover is paying for some (and sometimes all) of her living expenses.

The term "mistress" was originally used as a neutral feminine counterpart to "mister" or "master".

Historically the term has denoted a "kept woman", who was maintained in a comfortable (or even lavish) lifestyle by a wealthy man so that she would be available for his sexual pleasure. Such a woman could move between the roles of a mistress and a courtesan depending on her situation and environment. In modern times, however, the word "mistress" is used primarily to refer to the female lover of a man who is married to another woman; in the case of an unmarried man, it is usual to speak of a "girlfriend" or "partner". Historically, a man "kept" a mistress. As the term implies, he was responsible for her debts and provided for her in much the same way as he did his wife, although not legally bound to do so. In more recent times, she may be less, if at all, financially dependent on the man.

A mistress is not a prostitute: while a mistress, if "kept", may, in some sense, be exchanging sex for money, the principal difference is that a mistress has sex with fewer men and there is not so much of a direct quid pro quo between the money and the sex act. There is usually an emotional and possibly social relationship between a man and his mistress, whereas the relationship to a prostitute is predominantly sexual. It is also important that the "kept" status follows the establishment of a relationship of indefinite term as opposed to the agreement on price and terms established prior to any activity with a prostitute.

The historically best known and most-researched mistresses are the royal mistresses of European monarchs, for example, Agnès Sorel, Diane de Poitiers, Barbara Villiers, Nell Gwyn and Madame de Pompadour. The keeping of a mistress in Europe was not confined to royalty and nobility, but permeated down through the social ranks, essentially to any man who could afford to do so. Any man who could afford a mistress could have one (or more), regardless of social position. A wealthy merchant or a young noble might have a kept woman. Being a mistress was typically an occupation for a younger woman who, if she were fortunate, might go on to marry her lover or another man of rank.

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