A carving knife is a relatively big knife, around 21 cm and 39 cm (8 and 15 in.) in length.It is exactly named for what is built to function on. It's for carving a roast, a turkey, something where you are maneuvering and having to cut. A lot of people will use a carving knife just as their general everyday knife, which is hardly discouraged, but it does have a specific purpose.
In contrast to chef's knife which is much wider and it's meant for chopping and bigger quantities, carving knife is meant to cut in a specific area and where you may have to turn with it, so it's a much narrower blade. It's still kind of the basic shape, but just more narrow and a little bit more straight.
So implying you are carving a roast or turkey and you are already sliced through the breast. Now you have to maneuver a little bit. This exactly is the purpose of a carving knife.