N-COUNT (常指神话传说中)被(仙女)调换的婴儿 A changeling is a child who was put in the place of another child when they were both babies. In stories changelings were often taken or left by fairies. (常指神话传说中)被(仙女)调换的婴儿 [literary]
I have always felt like a changeling born into the wrong family.