Longman Dictionary of Contemporary English
EXAMPLES FROM CORPUS
▪ Which same meant, thought Markby, that he was saying Harriet wasn't a kept woman.
The Collaborative International Dictionary
kept \kept\ (k[e^]pt), imp. & p. p. of Keep.
Kept woman, Kept mistress, a concubine; a woman supported by a man as his paramour.
n. A woman who is supported financially by a lover (usually a married man).