Which term describes music characterized by a lack of melody and harmony?

The term "atonal" accurately describes music that lacks a clear tonal center, melody, or harmony. Atonal music does not adhere to the traditional structures and relationships found in conventional tonal music, making it distinct in its approach. In atonal compositions, the focus is often on other elements such as rhythm, texture, and dynamics rather than melody or harmony. This style became prominent in the early 20th century with composers like Arnold Schoenberg pioneering the use of atonality to explore new musical ideas.

On the other hand, "polyphonic" refers to music that consists of multiple independent melodies occurring simultaneously, creating a complex interweaving of musical lines. "Dissonant" pertains to a combination of tones that create instability or tension but does not inherently imply a lack of melody or harmony, as dissonance can occur within tonal music. "Secular" describes music that is not religious in nature but does not specifically relate to the absence of melody or harmony either. Therefore, atonality is the precise term for music that is characterized by its lack of melodic and harmonic clarity.