Foster parent and Wet-nurse

Foster parent noun - A person who acts as parent and guardian for a child in place of the child's natural parents but without legally adopting the child.

Wet-nurse and foster parent are semantically related. In some cases you can replace phrase "Wet-nurse" with "Foster parent", this phrases are similar.

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

Foster parent and wet-nurse are semantically related. Sometimes you can use "Foster parent" instead a noun phrase "Wet-nurse".