I’ve just moved into a one-storey shared villa complex, and my ceilings look like the picture shown, where the ceiling is not parallel to the floor (8′ high at one end, 11′ at the other)

My dad and my girlfriend’s parents called these vaulted ceilings, but from what I have found online I’m not sure that this really is a vaulted ceiling. It seems that cathedral ceilings require a central peak, which I don’t have (but the building does overall), and it seems that vaulted ceilings are rounded, created from arches, whereas mine is just a straight angle

Is “vaulted” just a technically inaccurate but colloquially acceptable term for this? or do I actually have a vaulted ceiling? or, none of the above? 

Just curious/confused

Thanks!