mistress Definition

mistress
noun mistresses

1. The female lover of a man married to another woman.

Thesaurus: lover, the other woman, kept woman, paramour, concubine, courtesan.
2. rather dated
A female teacher. Compare master.
Example: She is the French mistress
3. A woman in a commanding or controlling position; a female head or owner.

Thesaurus: proprietress, housekeeper, caretaker, schoolmistress, chaperon, matron, manager.
4. formerly
A term used when addressing any woman, especially one in authority. Compare Mrs.
Form: Mistress (especially)

Etymology: 14c in senses 2 and 3: French.