Atonality (noun)

Music that does not conform to a tonal system of harmony, and is not based on a central key or tonic note.

Origin:

Early 20th century: from a-1 + tonality.

Examples:

1. Atonality is a musical style characterized by the absence of a tonal center or key.
2. Composers such as Arnold Schoenberg and Anton Webern were among the first to experiment with atonality in music.
3. Atonality is a form of music in which the tonality is not defined.
4. Atonal music is often considered to be dissonant and lacking in a sense of key or tonality.
5. In the early 20th century, many composers began to explore atonality as a means of expanding the harmonic language of classical music.