GenocideHeart said:
They could also be called, more literally, 'Jyuujin', or 'Man-beasts'. That's the category that all beast-humans fall into - cat people, dog people, dragonmen, even lycanthropes.
Granted, the category is VERY large. Anything with a humanoid look, humanoid or higher intelligence and the ability to speak falls in it.
True, though the name "Kemono-musume", among the general fandom, refers more specifically to a subcategory of jyuujin.
In particular, "kemono-musume" is used for female humanoid characters with animal ears, likely a tail, some mannerisms characteristic of their species (e.g. catgirls preening, meowing, purring), and possibly paw-like hands and/or feet. Fur may be present, but it must be either barely noticeable, or not covering the majority of the body.
Catgirls are the most popular variant of "kemono-musume", even so far as to warrant their own sub-subcategory, "nekomimi-musume" ("cat-ears girl"), which means the character has cat ears, possibly a cat tail, and definitely has the mannerisms of a cat.
The easiest way to know whether or not a female character qualifies as a kemono-musume or not is to look at the face. Muzzle-shaped faces automatically disqualify one as such, though they are still
jyuujin.
Examples:
Sanada-san from
UFO Princess Walkure. Textbook example of a nekomimi-musume if there ever was one.
Felicia of Darkstalkers. She's on the far end of the spectrum, what with the digitigrade hindpaws, large claws, and visible fur. The difference made is that 1. she has a normal, human-shaped head, 2. the hands and feet are transformable, and 3. the fur does not cover all of her body and is situated to resemble a "swimsuit" fighting outfit.