What term describes the accuracy of pitch while singing or playing?

The term that best describes the accuracy of pitch while singing or playing is intonation. Intonation refers to how in-tune a singer or musician is with a given pitch or melody. It involves the precise control of pitch, ensuring that notes are sung or played correctly in relation to the desired frequency. Good intonation is crucial in creating harmony and maintaining the overall quality of music.

Modulation refers to the process of changing from one key to another within a piece of music and does not specifically pertain to the accuracy of pitch. Acapella involves singing without instrumental accompaniment and is not directly related to pitch accuracy. A round is a musical form where two or more voices sing the same melody but start at different times, which does not address pitch accuracy itself. Therefore, intonation is the correct term as it captures the essence of maintaining accurate pitch in performance.