'Servant girl' in the Bible

ThenPharaoh's daughter came down to the Nile River to bathe while her maids walked along the river bank. She saw the container among the reeds and sent a servant girl to get it.

and every firstborn male in the land of Egypt will die, from the firstborn of Pharaoh who sits on his throne to the firstborn of the servant girl who is behind the millstones, as well as every firstborn of the livestock.