a woman who has authority, control, or power, especially the female head of a household, institution, or other establishment.
a woman employing, or in authority over, servants or attendants.
a female owner of an animal, or formerly, a slave.
a woman who has the power of controlling or disposing of something at her own pleasure: mistress of a great fortune.
(sometimes initial capital letter)something regarded as feminine that has control or supremacy: Great Britain, the mistress of the seas.
a woman who is skilled in something, as an occupation or art.
a woman who has a continuing, extramarital sexual relationship with one man, especially a man who, in return for an exclusive and continuing liaison, provides her with financial support.
early 14c., "female teacher, governess," from Old French maistresse "mistress (lover); housekeeper; governess, female teacher" (Modern French maîtresse), fem. of maistre "master" (see master (n.)). Sense of "a woman who employs others or has authority over servants" is from early 15c. Sense of "kept woman of a married man" is from early 15c.
