What is the position/inversion called when referring to a triad's 6 or 6?

The position or inversion referred to when discussing a triad's 6 or 6 is known as the first inversion. In a triad, when it is in first inversion, the third of the chord is the lowest note, and the root is displaced above this lowest note.

For example, in a C major triad consisting of the notes C, E, and G, when the triad is in first inversion, it would be voiced as E (the lowest note), G, and then C. The term "6" in this context indicates that the interval from the bass note (E in this case) up to the root (C) spans a sixth.

This nomenclature is an essential part of music theory and allows musicians to identify and construct different chord structures. Understanding these inversions helps with proper voicing and smooth transitions between chords in compositions and arrangements.

The other options refer to different chord positions or inversions where the roles of the root and other chord tones are different:

• Root position has the root as the lowest note.

• Second inversion includes the fifth as the lowest note.

• Third inversion applies to four-note chords, which is not relevant here.