changelings

noun

1. 1

   In pre-modern European mythology, an infant that was secretly exchanged for a mother's own baby by an evil creature. (In British, Irish and Scandinavian mythology the exchanged infants were thought to be those of fairies, sprites or trolls; in other places, they were ascribed to witches, devils, or demons.)

2. 2

   An infant secretly exchanged with another infant by mistake or by human doing; swapling.

3. 3

   An organism which can change shape to mimic others.

4. 4

   A simpleton; an idiot.

5. 5

   One apt to change; a waverer.