A polydactyl cat is a cat with a congenital physical anomaly called polydactyly (or polydactylism, also known as hyperdactyly), a type of cat body type genetic mutation, that causes the cat to be born with more than the usual number of toes on one or more of its paw. Cats with this genetically inherited trait are most commonly found along the East Coast of the United States and in South West England.