*mer-, associated with crushing, pressing and oppressing, or according to other sources 'to rub away' or 'to harm'. Compare this to Finnish and Karelian, where the creature is roughly called "pressinger" (, ), or "ridinger" . Further, in Danish and Norwegian, the word for 'nightmare' is "mare ride" (, ); in Icelandic, the word for 'nightmare' is "mare tread", or "mare trample" ; whereas in Swedish and Finnish, the word for 'nightmare' is "mare dream" (, ).

However, other etymologies have been suggested. For example, Éva Pócs