Question: I wanted to highlight a particular chord of my [previous question](https://music.stackexchange.com/q/114106/77758) because it was bugging me a bit. What would you call a dominant triad over a subdominant bass, in pop/jazz roman numeral analysis? It could be seen as a `V7` in third inversion, but if you have a strong subdominant bass it doesn't really sound like it. But just calling it a `IV` seems... meh. Especially because we call the inverse, a subdominant triad over a dominant bass, a sus chord.

**Update**: Thanks all for your responses. As most of you have said, roman numeral analysis isn’t really suited for these kinds of chords. I might decide to just slash chords for bass and then come up with a different way to notate secondary chords and modulations in a functional manner. I don’t want to do this literally because that doesn’t make sense in a tonic-agnostic notation.

[![Sample](https://i.stack.imgur.com/MbtNF.png)](https://i.stack.imgur.com/MbtNF.png)

Answer: 
It's triads over a pedal. F, G/F, F. If tempted to call the second chord G7/F, take the idea a little further...

[![enter image description here](https://i.stack.imgur.com/HSiwn.png)](https://i.stack.imgur.com/HSiwn.png)

Wouldn't it be ridiculous to call that new chord A♭6/F? No, these are plain triads over a pedal and deserve to be named as such.

But I don't think Roman numbers deal with this very well. It likes everything to be functional.

(This, of course, would be a different matter. Here it IS a last-inversion G7.)
[![enter image description here](https://i.stack.imgur.com/cZGPU.png)](https://i.stack.imgur.com/cZGPU.png)
Normally the melody do-ti-la above IV (the subdominant) will be considered (the middle not e) as passing tone. Now together with parallels of 3rd and 6th we get a resoti (V) chord. I think it is most useful to consider this passage as a slash chord and it will help you to transpose it easily in other keys.

I think the idea of passing tones or suspensions 6-5;9-8;11-10 is more logical than the 3rd inversion of V7.