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Music theory definition

Diatonic

Belonging to the current key - using only its seven notes.

Stack a triad on every note

One per = the .

Learn it in context

This term is introduced in Unit 9: Diatonic harmony. Work through the explanations and exercises to connect the definition with music.

Harmony
The way notes sound together and how groups of notes move from one to the next.
Chromatic
Using notes outside the current key.
Roman numeral
A label for a chord by its scale degree: I, ii, V… Uppercase is major, lowercase minor.
Harmonic function
A chord's job in a progression: tonic (home), predominant (away), or dominant (pulling home).
Predominant
Chords like IV and ii that lead toward the dominant.
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