Tonic

The tonic is the main note of a scale and the tonal center around which a piece of music is organized. It serves as the natural starting and ending point of melodies and chord progressions. For example, in C major, the tonic is C. It gives the key its name and corresponds to the I degree in music theory. In a song, the tonic provides a sense of rest, stability, and resolution, contrasting with tension chords like the dominant (V).