■ noun
1》 a woman in a position of authority or control.
↘ Brit. a female schoolteacher.
↘the female owner of a dog, cat, etc.
↘ archaic a female head of a household.
2》 a woman skilled in a particular subject or activity: a ~ of the sound bite.
3》 a woman (other than the man's wife) who is having a sexual relationship with a married man.
↘ archaic or literary a woman loved and courted by a man.
4》 ( Mistress ) archaic or dialect Mrs.
Origin
ME: from OFr. maistresse , from maistre 'master'.