foster mother

American  

noun

1. a woman who takes the place of a mother in raising a child.

2. a nurse.

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foster mother British  

noun

1. a woman who looks after or brings up a child or children as a mother, in place of the natural or adoptive mother

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Etymology

Origin of foster mother

before 1000; Middle English; Old English

Example Sentences

As Laura, the foster mother in “Bring Her Back,” Ms. Hawkins turns the smile up to terrifying.

From The Wall Street Journal • Sep. 30, 2025

His foster mother encouraged him to go out to dances.

From BBC • Jul. 12, 2025

Justin and his two older siblings lived in a different home with a foster mother.

From Los Angeles Times • Apr. 4, 2025

You were a foster mother to a disabled adult for 13 years.

From Slate • Apr. 4, 2024

I knew our foster mother would gently scold me in the morning, but I just kept doing it.

From "Courage to Soar" by Simone Biles