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

Keep scrolling for more

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

One reason may be that foster and adoptive parents aren’t aware of them. Naomi Schaefer Riley, WSJ, "The White House Can Help Foster Kids," 9 Dec. 2018 By December, a state work group will submit its own list of recommendations to the Washington Legislature to close the academic achievement gaps for foster and homeless students by 2027. Neal Morton, The Seattle Times, "Washington’s homeless students face steep academic struggles," 2 Oct. 2018 Steppe and his team of eight part-time mentors and music and video producers work six days a week with mostly teens ages 14 to 18 who are in homeless shelters, foster care and the juvenile justice system. Pam Kragen,, "David's Harp strikes a note with at-risk teens," 30 May 2018 Glenn’s foundation, the Brighter Generation Foundation, delivers supplies, resources and access to education for homeless and foster children. Clarence E. Hill Jr., star-telegram, "Former Cowboys and Buckeyes raising money for Terry Glenn and Ron Springs foundations | Fort Worth Star-Telegram," 16 May 2018 Little is known about the children’s lives in Texas because foster care records are confidential and court documents regarding adoption are generally sealed. Allie Morris, San Antonio Express-News, "Six children involved in fatal California crash adopted from Houston-area," 6 Apr. 2018 Much of his work involved reviewing operations of the Health and Family Services Cabinet, which oversees foster care and adoption in Kentucky. Deborah Yetter, The Courier-Journal, "Kentucky's 'adoption czar' is gone 7 months after Gov. Bevin gave him a $240,000-a-year job," 16 Jan. 2018 The baby was given up for adoption, while the girl now resides in foster care. Fox News, "Convicted molester's girlfriend admits letting him assault daughter, 10, resulting in pregnancy," 28 Sep. 2018 Sorting out immigration status is an important part of transitioning from foster care to adulthood. Elizabeth Yaeger, Teen Vogue, "How Immigration Status and Foster Care Are Connected," 24 May 2018

Recent Examples on the Web: Verb

Low-Hanging Fruit Amadeus is officially called a Global Distributed Systems (GDS), and is one of three that fosters communication between airlines and various players in the travel industry. Sam Blum, Popular Mechanics, "A Hacker Exposed the Ancient Flaw That Makes Airlines So Hackable," 17 Jan. 2019 These could be textiles, sculptures, or paintings, each helping to foster individuality. Sienna Fantozzi, House Beautiful, "Everything You Need To Know About Bohemian Design," 19 Oct. 2018 Skip the giant parties for now and circle up with a smaller group for a book club, an intimate dinner—something that will foster a deeper conversation or debate. Catherine Urban, Bon Appetit, "Your May Horoscope Knows That What Lies Ahead Is Actually Just Potato Chips," 1 May 2018 In large populations, natural selection efficiently weeds out deleterious genes, but in smaller groups like those early humans, harmful genes that arise—including those that foster mutations—can survive. Elizabeth Pennisi, Science | AAAS, "Why microbes are better than people at keeping DNA mutations at bay," 11 Apr. 2018 Health insurers were hiking their rates dramatically and might pull out of the market altogether if the uncertainty fostered by Trump continued. Dylan Scott, Vox, "Lamar Alexander, pillar of Washington’s old guard, is retiring from the Senate," 17 Dec. 2018 Swayed by general manager Dayton Moore’s honesty and the familiarity fostered by area scout Jim Buckley, Singer and his family came to Kansas City to sign a contract with a bonus of $4.25 million. Maria Torres, kansascity, "'He is gonna be what people come to see': Royals sign, introduce top pick Brady Singer," 3 July 2018 There is also a wide perception among patients, fostered by many eye doctors who do the surgery, that the procedure is virtually foolproof. Author: Roni Caryn Rabin, Anchorage Daily News, "Blurred vision, burning eyes: This is a Lasik success?," 12 June 2018 Jaime Wilson, a Seven Lakes High School history teacher, has joined a mission fostered by Katy Veterans of Foreign Wars Post 9182 to make sure that people don’t forget about the Vietnam War and the men and women who fought in it. Karen Zurawski, Houston Chronicle, "Katy VFW recognizes Seven Lakes HS teacher," 5 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.

See More

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

Adjective and Verb

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

Keep scrolling for more

Learn More about foster

Dictionary Entries near foster







foster care

Statistics for foster

Last Updated

15 Feb 2019

Look-up Popularity

Time Traveler for foster

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

See more words from the same century

Keep scrolling for more

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

Keep scrolling for more

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

Comments on foster

What made you want to look up foster? Please tell us where you read or heard it (including the quote, if possible).


to deny responsibility for

Get Word of the Day daily email!

Test Your Vocabulary

What did you just call me?! A Quiz

  • rows-of-various-emoji
  • If a member of the audience describes your speech as bombastic, does that person mean it is:
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!