Yes, the amplitude of a sound wave can be defined in terms of pressure. In acoustics, the amplitude of a sound wave refers to the maximum displacement or variation from the equilibrium position of the medium through which the sound wave is propagating. In the case of a pressure wave, the amplitude is related to the maximum variation in pressure caused by the sound wave.
When a sound wave travels through a medium, it causes regions of compression (increased pressure) and rarefaction (decreased pressure). The amplitude of the sound wave corresponds to the maximum deviation from the average or ambient pressure in these regions.
The relationship between the amplitude of a sound wave and the pressure variation depends on the specific characteristics of the wave and the medium. In a simple sound wave, where the pressure variation is sinusoidal, the amplitude can be measured as the difference between the maximum and minimum pressure points.
It's worth noting that the amplitude of a sound wave is distinct from the intensity or loudness of the sound. The intensity of a sound wave is related to the energy carried by the wave per unit area perpendicular to the direction of wave propagation. While the amplitude is one factor that contributes to the intensity, other factors such as the distance from the sound source and the medium's properties also play a role in determining the sound wave's overall intensity.