English Reference
verb · adjective

foster

v. · adj.
US /ˈfɑstɝ/ UK /fˈɒstɐ/ fos·ter UK spelling fostered, Fosters

  1. 01 B2 Upper Intermediate

    v.to help a feeling, an idea, or a skill grow and become stronger.

    v.to promote the growth or development of something; to cultivate a specific environment or quality.

    Simple

    The teacher tried to foster a sense of curiosity in her students.

    In context

    The government introduced new tax incentives designed to foster innovation within the renewable energy sector.

  2. 02 B2 Upper Intermediate

    v.to take a child into your family for a period of time without becoming their legal parent.

    v.to provide parental care for a child who is not one's own by birth or legal adoption, typically on a temporary basis.

    Simple

    They have fostered over ten children while their birth parents were unable to care for them.

    In context

    Social services worked closely with the couple as they prepared to foster a sibling group with complex emotional needs.

  3. 03 B2 Upper Intermediate

    adj.used to describe a family or child involved in a temporary care arrangement.

    adj.denoting a relationship or person involved in the temporary care of a child by someone other than their legal parents.

    Simple

    She is still very close to her foster brother even though they are adults now.

    In context

    The legislation aims to provide better long-term support for foster parents who commit to caring for children with disabilities.

Usage foster development

Yet, likes are increasingly viewed as a way to foster negative feelings, particularly among young people.

BBC News· 16 Aug 2026

Sixteen-year-old Dusty and her little sister Poppy have been through multiple foster placements.

The Guardian· 22 May 2026

English surname, reduced from Forster; also from the noun foster.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C1 · Advanced
Frequency Common
Updated