[strumminsix]

The term "inversion" only applies if the added lowest note is a chord tone. You can also add a non-chord tone. For example, C/D where the C isn't a C9.

I always understood it to be a chord in which the lowest note is not the root. How can a tone that is part of, and played with a chord not be considered a chord tone? iow what is a "non-chord" tone, in the context of ...a chord?

I think you guys are saying the same thing very differently. May I try?

Inversion = playing only the notes of a chord but the root is not the lowest tone played instead the 3rd or 5th is the lowest tone.

[Rusty the Scoob]

Yep, S6's definition is what I meant. IMHO it doesn't qualify as an inversion if the note in the bass isn't part of the chord itself... I.E. if you have a C Major with a D in the bass, that's a slash chord but not an inversion. Or even a C Major with a Bb in the bass. But a C7 with a Bb in the bass would qualify as an inversion.