Boginka
In Polish pagan mythology, boginki are female spirits or demons of wild nature: forest, field, mountains, or water and is often a personification of the forces of nature. The word literally means "minor goddess" in Polish and may be translated as "fairy" or "nymph". They were usually imagined as either ugly old hags or pretty young girls, usually naked. They are usually evil.
Some boginki are rusałka, vila, dziwożona, łaskotałka,, or nawka. The term "boginka" started to be applied to any of them.
Boginki can steal a human child and substitute them. Such substituted child is called boginiak, płonek , podrzutek, or odmieniak. Often children with mental disabilities were thought to be such.
There are various folk means to fend off boginki.