A Slavic version of mare (mora), as in nightmare.
Bukovica, Narodni Zivot i Obicaji / (Bukovica, Folk Life and Customs)
by Vladimir Ardalic
(published in 1899; 1900, 1902)
(The text is a)antique; b) in dialect; c)in cyrillic.)
"The name mora comes from 'to be racked/ to lie heavy upon' (morenje), when a being (child, person) is assailed, it would be said, now he will tire (umoriti). People believe, there is this, that, and other, but for the mora, they mostly hold she exists. A male can not be a mora, nor a morac.(My note: male version of mora)"
..."Mora(s) are born from witches, and then, not even from them: which ever child is born in a blue placenta, each one becomes a mora. While she is a mora, she cannot be a witch nor eat hearts, but can only weigh on young children." ...
... "One can recognise, who is a mora, because she has faintly dark hairs on her upper lip. As soon as she gets married, she immediately becomes a witch. "
..."Who eats a lot of onions, the mora won't go to him; some even rub themselves at night, upon going to sleep, with onion."
"The best to do, upon seeing either a witch or a mora, is to extend horns after her, or, with the index finger of the left and right hands, make the sign of the cross, and look at her above it, wether she be with her front or back turned to you."
How to deal with a Mora or a Witch