A breed of cat, related to the Manx - both are native to the Isle of Man. Cymrics are solidly built, and have round heads, widely spaced ears, and round eyes. Their rear legs are longer than their front legs, so their back tends to arch. A completely tailless Cymric is called a "rumpy," but like Manx cats Cymrics may have stubby tails or even tails almost as long as those of normal cats. Their coat is longer than a Manx's, and requires grooming a couple of times a week - brushing or combing will suffice. They come in all patterns, including tabby, calico, and other standard cat patterns. Some Cymrics develop physical problems related to their spinal deformity and lack of tail. They tend to be very good with children. Although Manx cats have been popular in the United States for decades, the Cymric was not noticed until the mid-1970s. The Canadian Cat Association was the first to recognize the Cymric for competitions, and since then other associations have followed suit, except for the Cat Fanciers' Association which includes the Cymric as a longhaired variety of the Manx.

Sources:
http://www.petsmart.com/aspca/cats/cymric.shtml
http://www.catsandkittens.com/breeds/cymric.shtml