I believe the term you are looking for is called an agora.
The answer is parallel.
To add, absolute water depth has nothing to do with the difference between shallow and deep-water waves. On the other hand, the ratio of the water’s deep to the wavelength of the wave is that one that determines it. A deep-water wave’s water molecules proceed in a circular orbit while the orbit of the molecules of shallow-water waves molecules’ orbit are elliptical.
