The measure of a wave moving up and down is called amplitude.

Here's a breakdown:

* Amplitude: This is the maximum displacement of a point on the wave from its equilibrium position. It's essentially the height of the wave from the "middle" point to its highest or lowest point.

* Wavelength: This is the distance between two consecutive crests or troughs of the wave.

* Frequency: This is the number of waves passing a fixed point in a given amount of time.

So, while all these properties describe different aspects of a wave, amplitude specifically describes the up-and-down movement.