Yes, it's what we visual folks refer to as the 'visible surface' of the Sun. So, because of the scale height, this surface is a bit fuzzy, some +/- 100 km. Which is some 7000 x shorter than the radius of the Sun, which is why the solar disc's edge looks so sharp in the sky.
You can think of the visibility in fog: if it says that visibility is 200 m, that doesn't mean that the fog is a hard wall at that distance. It's fuzzy.
