Werecats (also written in a hyphenated form as were-cats) are creatures of folklore, fantasy fiction, horror fiction, and occultism that are generally described as shapeshifters similar to werewolves that, instead of a wolf, turn into a creature that is based on some species of feline. The species involved can be a domestic cat, a tiger, a lion, a leopard, a lynx, or any other type, including some that are purely fantastical felines. Typically, an individual werecat can only transform to one unique feline, not to a number of different species, and each individual type of werecat may be known by a more species-specific term such as "weretiger". The word "werecat" was not coined until the late 19th century, so it was not directly used in legends from earlier eras, only by later folklorists' commentary.

Source: Wikipedia