Velocicline
The interphase between two media traveling at different velocities.
In rafting it is also known as an eddy fence. Velocicline is, where water travels around a boulder in a river and interacts with the slow moving water behind the boulder. It makes a line of turbulent water. Similar to thermoclines and haloclines. Which is the interphase of two different temperature media and the interphase of two different salinity media, respectvely.