What is an oblique shape?

If we're talking in purely geometric terms:

If the edges of a prism/cylinder make a right angle with the base, it is called a right prism/cylinder. If not, it is an oblique prism/cylinder...it will look as if it were slanting to one side instead of standing straight.

Similarly, if the top vertex of a pyramid/cone is directly above the center of the base, it is a right pyramid/cone. Otherwise, it is an oblique pyramid/cone. Again, it will look a bit askew.