From Longman Dictionary of Contemporary Englishsingle parentˌsingle ˈparent noun [countable] SSFFAMILYa mother or father who looks after their children on their own, without a partner SYN lone parent
Examples from the Corpus
single parent• Clockwise from above: Tatiana is a single parent.• But it's tricky if you're a single parent - isn't that a ghastly expression?• A single parent with two or three children in California would lose $ 1 in income.• Priority for assistance will be given to senior citizens, disabled and single parent families.• Liz, 36, was left the single parent of Amy, now five. 