Yes, celeriac and celery root are one and the same vegetable except that it has two names. The reason it has two names is that the name celery root is somewhat misleading. One would think that a celery root is the root of the celery plant. This, however, is an incorrect assumption. It is an entire vegetable as celery is a stalk vegetable while a celery root is a root vegetable. Therefore, renaming it celeriac was a much simpler solution!