Beregynja - creature of Slav. mythology; theoret. IE. *bherg-uniy-a, most surely however, after the example Old Russ. peregynja, from beregь "(high) bank, coast" (see:
Przeginia), kind of nymph (secondarily - water); originally creature connected with worship of Slavonic Goddess
Mokoš - Earth; maybe Mokoš was called beregynja oneself (properly: Peregynja; compare to
Jörd-
Fjörgynn[?]); see also:
Perperuna.