Which term describes the measurement of how loud a sound is?

The term that effectively describes the measurement of how loud a sound is is loudness. Loudness refers specifically to the perception of sound intensity by the human ear, which is influenced by the sound's amplitude and frequency. It is a subjective measurement, meaning that it can vary between individuals depending on their hearing ability and environmental factors.

Volume often relates to the level of sound output on devices but does not capture the subjective experience of sound loudness in the same way. Pitch describes the frequency of a sound and how high or low it is perceived, while frequency indicates the number of vibrations or cycles per second in a sound wave, measured in hertz. Both pitch and frequency are more about the tonal qualities of sound rather than its loudness.