I googled "white cairn terrier" and all of the images were of west highland white terriers.
Yes and no, the West Highland White Terrier, the Scottish Terrier, and the Cairn Terrier, were originally defined as the white, black and "other" colored pups from short-legged terrier litters in Scotland. Since that time, these "varieties" have diverged into three distinct breeds with other differences than color – like the Cavalier King Charles Spaniel diverged from the English Toy Spaniel, the American Cocker diverged from the English, etc.
Purebred Cairns today do not come in white, so the closest thing to a purebred white Cairn would be it’s cousin, a purebred Westie, which only comes in white.
Tags: Westie, west highland white terrier