The Slavic male water spirit said to live in rivers and lakes is the Vodyanoy.
The Vodyanoy is a freshwater spirit whose name literally relates to water. Folklore places him in deep pools, whirlpools, ponds, lakes, and river bends, especially near watermills. He is often imagined as an old man with a swollen belly, green hair or beard, and clothing made from reeds, rushes, or algae.
Stories portray him as powerful and dangerous when angered. He may break dams, damage mills, drown people or animals, and drag victims into an underwater dwelling. Fishermen, millers, and beekeepers were said to leave offerings to keep him calm. Some tales also describe him as a shapeshifter or ruler of aquatic creatures.
The Vodyanoy is commonly confused with the Rusalka, but the Rusalka is generally a female water-associated spirit or drowned ghost. Leshy belongs to the forest, while Kikimora is primarily a household or swamp spirit. Czech and Slovak traditions use the related name Vodník.