How does one differentiate AC signals that only go to GND vs those that goto (-)Vss

[matrixofdynamism]

All dynamic signals are called AC signals. These include the single ended and differential signals.

However, AC signals may oscillate between power supply and ground as well as positive rail and negative rail. Is there a naming convention to differentiate these two types of AC signals? I guess both are going to be considered single ended anyway, since they have a single fixed reference called ground. It makes sense to have name for them since some circuits will not work with signals that go below ground but others will.

 

[FvM]

All dynamic signals are called AC signals.

Maybe in some context. I won't do so and distinguish between AC and general pulse signals. AC signals have either zero mean value, or the mean value/DC offset doesn't count.

For the other question, we could possibly talk about unipolar and bipolar signals.