What is the third?

What is the third?

• A. The middle note of the triad
• B. The lowest note
• C. The highest note
• D. The interval between root and top

Answer: (A)

In a triad, you build the chord by stacking notes in intervals of thirds above the root. The note that sits a third above the root is what we call the third, and in a standard root-position triad that note ends up as the middle pitch. For example, in C major the notes are C (root), E (third), G (fifth). The interval from C up to E is a third, so E is the third—and it’s the middle note here. The other descriptions describe other positions or intervals (the lowest would be the root, the highest the fifth, and the interval from root to top is a fifth), so the middle note is the best characterization of the third. If the chord is inverted, the bass might be the third, but the note that is a third above the root remains the third.

In a triad, you build the chord by stacking notes in intervals of thirds above the root. The note that sits a third above the root is what we call the third, and in a standard root-position triad that note ends up as the middle pitch. For example, in C major the notes are C (root), E (third), G (fifth). The interval from C up to E is a third, so E is the third—and it’s the middle note here. The other descriptions describe other positions or intervals (the lowest would be the root, the highest the fifth, and the interval from root to top is a fifth), so the middle note is the best characterization of the third. If the chord is inverted, the bass might be the third, but the note that is a third above the root remains the third.