Since Canon USA website calls the 17-40 L an Ultra Wide Zoom, the 24-70 II L a Standard Zoom, the 14mm L an Ultra Wide Lens and the 20mm a Wide Lens I would say that it is up to your own preference since Canon itself seems to label lenses by their own preference.
Canon even put the label "Wide" on the 15mm fisheye.

For me if someone says "Ultra Wide" they are making that designation because of the distortion you get with very wide lenses and it is understood. Not because it met some magical designated lens length.

Another designation "Super Telephoto" is meaningless, except that you must have "Super" strength to carry the pile of cash that it is going to take to buy one of these lenses. Or maybe just a "Super Fat" bank account.