Foster-mother and Wetnurse

Foster-mother noun - A woman who is a foster parent and raises another's child.

Wetnurse and foster-mother are semantically related. In some cases you can replace term "Wetnurse" with "Foster-mother", this terms are similar.

Wetnurse noun - A woman hired to suckle a child of someone else.

Foster-mother and wetnurse are semantically related. You can use "Foster-mother" instead a noun "Wetnurse".