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.
例句
I have always felt like a changeling born into the wrong family.我一直感觉自己小时候被调包过，不是这一家的人。
英英词典释义
Noun
1. a person of subnormal intelligence
2. a child secretly exchanged for another in infancy