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

The foster mother, who told The Times she did not want to be interviewed but talked from her doorstep in Palmdale, said she had been trying to adopt Justin and his two siblings.

From Los Angeles Times • Jul. 22, 2024

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

From Slate • Apr. 4, 2024

I sing the lullaby after her, my foster mother.

From "What the Night Sings" by Vesper Stamper