The rusalka (plural: rusalky; Cyrillic: русалка, plural: русалки. And loskitnytsa "tickler" or "she who tickles". Is a mythological female figure in many Slavic peoples, who can appear as a water deity; a drowned woman or a corpse; sometimes characterized as a nymph. They are usually the spirits of the dead, usually of the female sex. The appearance of a rusalka is predominantly humanoid, ranging from beautiful to ugly, sometimes with the addition of features that are not inherent to humans, even animal features. The mavka is considered to be related to rusalky.The image of mermaids has intertwined the features of fertility spirits (field rusalky), water (river rusalky) and the idea of "impure" dead people. Rusalky and keepers in Proto-Ukrainian paganism took care of the fertility of the field. The center of localization of the rusalka cult in Ukraine is considered to be Polissya.
The popular modern image of a rusalka as a girl with a fish tail corresponds to the creatures of Western European mythology - undines and mermaids, and comes from fiction.