In Japanese folklore, a nekomata is a cat yōkai whose tail splits into two as it grows old.
Nekomata are commonly described as supernatural cats with two tails, increased intelligence, and magical abilities. Folklore often places their transformation after a domestic cat has lived for many years or reached an unusually large size.
Nekomata are related to bakeneko, another Japanese cat yōkai, and the two are sometimes confused. Bakeneko are generally described as transformed or supernatural cats without the defining two-tailed form, while nekomata are specifically associated with the split tail.
Some traditions place nekomata in households, while others describe mountain-dwelling nekomata that have become especially dangerous. The related kasha is a corpse-stealing catlike yōkai, but it is not simply another name for nekomata.