What does the term 'tessitura' refer to in music?

The term 'tessitura' specifically refers to the range within which most of the notes of a piece of music lie, particularly in vocal music. It is often associated with the section of the vocal range that is most comfortable and pleasing for a singer to perform. This concept is essential for understanding how to properly categorize voices and select appropriate repertoire for singers, as well as for composers to write music that suits specific vocalists.

While the overall range of a musical piece might encompass a wider set of notes, tessitura focuses on where the bulk of the music resides sonically, typically pointing to the notes that are utilized most frequently and are most conducive to the singer's comfort. The distinction is crucial because a piece may have a wide overall range but still have a specific tessitura that demands attention to the singer's vocal health and aesthetic quality.