If the bass is held and considered the non-chord tone, I think the only traditional non-chord tone labels available are suspension or retardation, but those technically require resolution which doesn't happen in the example.
You could flip your non-chord tone labeling and call the bass tone the consonant tone and the treble voices the non-chord tones.
Dropping some voices to simplify and shifting some metrical placement we can get the following which is a basic escape tone.
Shift those notes metrically to get back to your example...
...add the additional voices and you might consider this some kind of accented, triple escape tone group...
Personally, I think my explanation above is trying to shoe-horn the music into a traditional non-chord tone identity, but I thought it might be valuable to try identifying an appropriate non-chord tone.
(One might grope further and find a combination anticipation in the G
and passing tones in the C E
.)
While an escape tone might - kinda, sorta - fit on paper, I don't think this provides a satisfactory explanation.
Why isn't it satisfactory? Because we first need a notion of what is dissonant and that is a matter of style!
Slight digression: in basic blues we use primary triads I, IV, V
but all harmonized as dominant-seventh chords where there is absolutely no need to resolve the sevenths. In other words you can say the sevenths in those chords are not considered dissonances. I think you can also say the tritone isn't dissonant in blues harmony, certainly not in the common-practice era sense.
Perhaps we can approach this music example in a similar way.
I think in some pop music styles there is a kind of primary chord superimposed harmony where just about any pattern outlining the primary chords of a key can be combined with another such pattern without the two patterns necessarily aligning vertically. Any such combination is deemed consonant. It's sort of like pandiatonicism except it focuses on the primary chords. I don't know any musical term to describe it.
In the example we clearly have V IV I
in the treble part over dominant and tonic tones in the bass. Both patterns separately are simple, direct outlines of the primary harmonies of G
major. The fact that the middle bar has a "mis-aligned" C
chord over a D
in the bass doesn't represent a dissonance. Any combination of the primary harmonies will be considered consonant.
I suppose if we are trying to escape from using Roman numeral analysis or jazz symbols on this (and I think we should) instead of writing V I
or D C/D G
or something like that, it would just be G major
and then the analysis focus might shift to rhythm or changes to the overall tonal center.
This isn't my own original idea. I first read it somewhere as an explanation of harmony in African Highlife music. It makes sense to me as a description of that musical style and I think it can also apply to rock and other pop music.