fos·​ter | \ˈfȯ-stər, ˈfä-\

Definition of foster 

(Entry 1 of 4)

: affording, receiving, or sharing nurture or parental care though not related by blood or legal ties They are foster parents to three foster children.


fostered; fostering\ˈfȯ-​st(ə-​)riŋ, ˈfä-​ \

Definition of foster (Entry 2 of 4)

transitive verb

1 : to give parental care to : nurture They are considering fostering a child.

2 : to promote the growth or development of : encourage fostered the college in its early years policies that foster competition


biographical name (1)
Fos·​ter | \ˈfȯ-stər, ˈfä-\

Definition of Foster (Entry 3 of 4)

Stephen Collins 1826–1864 American songwriter


biographical name (2)

Definition of Foster (Entry 4 of 4)

William Z(ebulon) 1881–1961 American Communist

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Other Words from foster


fosterer \ˈfȯ-​stər-​ər, ˈfä-​ \ noun

Examples of foster in a Sentence


Such conditions foster the spread of the disease. Would you consider fostering a child?

Recent Examples on the Web: Adjective

In season 1, we're told that Burnham was a ward of the Vulcan Sarek, Spock's father, and fans have been wondering how Spock never mentioned his foster sister Burnham during his entire tenure in Starfleet and beyond. Darren Orf, Popular Mechanics, "Everything We Know So Far About 'Star Trek: Discovery' Season 2," 5 Sep. 2018 Despite a 30-day deadline to re-unify families, about 570 children still remain in shelters or foster care, according to NBC News. Cynthia Drescher, Condé Nast Traveler, "How to Use Your Air Miles to Help Families Separated at the Border," 8 Aug. 2018 At least one of the young migrant children sent to Maryland facilities after being separated from family members at the southwest border is expected to be reunited with relatives on Tuesday, a foster agency involved in the process said. Ian Duncan,, "At least one of the youngest migrant children sent to Maryland will be reunited with family by court deadline," 10 July 2018 In New York City, where a debate has been unfolding for several months on the best way to integrate schools, some schools give admissions priority to children who are poor, in foster care, affected by incarceration or English language learners. Michelle Hackman, WSJ, "Rollback of Affirmative Action Guidelines Could Reshape K-12 School Districts," 14 July 2018 One child, who would qualify for U.S citizenship because Gelernt said his mother is American, has been in federal foster care for more than a year. Lomi Kriel, San Antonio Express-News, "Half of migrants under 5 reunited with parents, though rest remain ‘ineligible’," 12 July 2018 In a number of states, officials now plead for more households to take in foster kids and give them the essential experience of a stable home. The Christian Science Monitor, "Extending compassion beyond migrant kids," 26 June 2018 Juana is set to head to New York City to be with her husband and 15-year-old daughter, who recently was released from foster care, according to group organizer Julie Schwietert-Collazo. Lara Korte, WSJ, "New York Volunteers Win Release for Two More Migrants Separated From Children," 10 July 2018 Trinity House helps fill a void for those 16 to 21 who are aging out of foster care, housing up to 10 young men at a time. Maureen C. Gilmer, Indianapolis Star, "Trinity House will be home to young men aging out of foster care," 6 July 2018

Recent Examples on the Web: Verb

That’s the feeling that Qualcomm, Verizon, and AT&T are trying to foster. Sean Hollister, The Verge, "5G is weeks away — and Tuesday marks its first real test," 30 Nov. 2018 The multimedia professional sought to foster the creativity of children who participated in her workshops via an art installation called the Healing Garden, and through the interplay of light, colour and texture. Houston Chronicle, "ART FEEL: Digital collage art with Sue Burke Harrington," 22 June 2018 If fostering isn’t in the picture, consider volunteering at one of the city's animal care facilities. The Star-telegram Editorial Board, star-telegram, "The animal shelter is full again. Here’s how you can save some lives," 19 June 2018 Just a few blocks away in Wright Square, a revered Native American chief, who fostered peace in the new territory, was honored and buried in what was then a cemetery. Condé Nast Traveler, "8 Most Haunted Cities In America and Why You Should Visit," 18 Oct. 2018 Several spoke to the positive, genuinely kind atmosphere these online communities foster. Natalie Lampert, Marie Claire, "Why Women Reeling From Miscarriage Are Turning to the Web," 1 Oct. 2018 Dorsey’s leadership style fosters caution, according to about a dozen people who’ve worked with him. Casey Newton, The Verge, "Twitter’s fear of making hard decisions is killing it," 17 Aug. 2018 Large, unused spaces designed for social functions foster isolation instead. Kate Wagner, Curbed, "Our homes don’t need formal spaces," 11 July 2018 What does striving for adoption, or fostering, look like for a Black couple in a working class household?, "TV Has Made Major Strides With Gay Dads — Except For This Big Problem," 14 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'foster.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of foster


before the 12th century, in the meaning defined above


12th century, in the meaning defined at sense 1

History and Etymology for foster


Middle English, from Old English fōstor-, from fōstor food, feeding; akin to Old English fōda food


see foster entry 1

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Dictionary Entries near foster







foster care

Statistics for foster

Last Updated

6 Dec 2018

Look-up Popularity

Time Traveler for foster

The first known use of foster was before the 12th century

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More Definitions for foster



English Language Learners Definition of foster

 (Entry 1 of 2)

—used to describe a situation in which for a period of time a child lives with and is cared for by people who are not the child's parents



English Language Learners Definition of foster (Entry 2 of 2)

: to help (something) grow or develop

: to provide the care that a parent usually gives to a child : to be or become the foster parent of a child


fos·​ter | \ˈfȯ-stər \

Kids Definition of foster

 (Entry 1 of 2)

: giving, receiving, or offering parental care even though not related by blood or legal ties a foster parent a foster child a foster home


fostered; fostering

Kids Definition of foster (Entry 2 of 2)

1 : to give parental care to

2 : to help the growth and development of We're trying to foster a sense of responsibility.



Legal Definition of foster 

(Entry 1 of 2)

: affording, receiving, or sharing nurture or parental care though not related by blood or legal relationships a foster child a foster parent

fostered; fostering

Legal Definition of foster (Entry 2 of 2)

: to give parental care to

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More from Merriam-Webster on foster

Rhyming Dictionary: Words that rhyme with foster

Thesaurus: All synonyms and antonyms for foster

Spanish Central: Translation of foster

Nglish: Translation of foster for Spanish Speakers

Britannica English: Translation of foster for Arabic Speakers

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