Question of 養子 Meaning

Why is “Foster Child” not included?

There are other terms that mean “foster child”, such as 里子 (さとご), but 養子 doesn’t look like it does.

You can email and suggest it as a synonym

I didn’t know either, but it seems “adoptive child” and “foster child” are in fact not synonymous. “Adoptive child” is a child who has been adopted, while “foster child” is in general any child who isn’t being raised by their biological parent(s) (and consequently by someone else).


I realized I didn’t give enough detail to my answer, in light of a term that just came up in my reviews.

@obskyr makes the point, in that an adopted child and a foster child are different things. However, you may be thinking that 養子 should be “foster child” because WaniKani has the primary meaning of 養う set as “to foster”. In this case, it’s 養う that’s slightly off, as it doesn’t strictly mean “to foster”.

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養う does mean “to foster,” it’s just that it’s broader than just taking care of children.


I find it an interesting reflection of old Japanese cultural norms that 養子, “adopted child”, also means son-in-law, where as 義理の娘, “duty” or “obligation” daughter, means daughter-in-law.

I guess since son-in-laws were “adopted”, they can’t be foster children.

I just run into this issue, then found this topic and your explanation.

However, as a non native, I see absolutely no difference between “foster child” and “adopted child” hence I happily added “foster child” as a synonym for this word :smiley:

I feel that WK tries to go way into to much detail with vocabulary…

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I’m not sure what the best word for 養子 is, but those aren’t interchangeable. You wouldn’t call an adopted child a foster child, or vice versa. They’re related, I guess.

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Let me put it this way: for me, for all intents and purposes, they are similar enough to not be bothered to distinguish them (same with military ranks for example)…

I just found The Differences Between Foster Care and Adoption

In fact, many prospective parents confuse the two when they attend foster or adoptive parent training classes.

So it’s not only a Japanese / language problem but in general people don’t pay all that much attention to the difference…

You can add your own synonyms to a word. I added “foster child” to this one as well.


Yup, done it as well…