other woman
noun /ˌʌðə ˈwʊmən/
/ˌʌðər ˈwʊmən/
[usually singular]- a woman with whom a man is having a sexual relationship, although he already has a wife or partner
- Jean Menkes plays the president's wife and Fiona Handley plays the other woman.
- She was the ‘other woman’ in this family drama.