mistress

/ˈmɪstrəs/

an adulterous woman; a woman who has an ongoing extramarital sexual relationship with a man

Chinese meaning: 情妇；主妇

The scandal revealed that the politician had a secret mistress for years.

丑闻揭露该政客多年来有一位秘密情妇。

She was the mistress of the household, managing all domestic affairs.

她是女主人，管理所有家务。