To foster is to nurture something. A teacher could foster creativity by providing crayons to every student. You can also foster a child, which means the child lives in your home for a time.

You may have seen photos of a cat taking care of a baby rabbit, or a pig nursing a litter of puppies: those are little foster families. Foster can be a verb (to foster someone or something) or an adjective used to describe a foster family, child, or parent. The word is from the Old English fostrian meaning "to supply with food, nourish, support," which sounds like what those mama hogs were doing. Unlike adopt, foster has a time limit.

Definitions of foster
  1. adjective
    providing or receiving nurture or parental care though not related by blood or legal ties
    foster parent”
    foster child”
    foster home”
    synonyms: surrogate
    of parents and children; related by adoption
  2. verb
    promote the growth of
    synonyms: further
    see moresee less
    type of:
    advance, boost, encourage, further, promote
    contribute to the progress or growth of
  3. verb
    help develop, help grow
    synonyms: nurture
    see moresee less
    keep going, patronage, patronise, patronize, support
    be a regular customer or client of
    serve, serve well
    promote, benefit, or be useful or beneficial to
    type of:
    inspire with confidence; give hope or courage to
  4. verb
    bring up under fosterage; of children
Word Family

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