What is the name of scale degree 3?

Scale degree 3 is referred to as the Mediant. In the context of the major scale, the Mediant is the third note of the scale and is positioned halfway between the tonic (first scale degree) and the dominant (fifth scale degree). This degree plays a crucial role in establishing the tonality of a piece, as its relationships to other scale degrees can create a rich harmonic texture.

For instance, when harmonizing a melody, the Mediant can help define whether the piece is in a major or minor key, depending on whether it is used in a major or minor context. It often serves as a pivotal part of chord progression, especially within cadences and leads to resolution points in music.

Understanding the functions of the Mediant in different harmonic contexts can enhance a musician's ability to compose and interpret music effectively, especially in the genres that involve rich harmonic textures or modulations.