WordNet
foster-mother
n. a woman who is a foster parent and raises another's child
Usage examples of "foster-mother".
Then to cover his emotion he told them of the silver cup he had got from his foster-mother that was a replica of the one owned by the hermit of Bawn na Drum.
But for GalacTech, it meant that human bioengineering experiments could at last be carried out without involving a lot of flaky foster-mothers to carry the implanted embryos.