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.

phone: why don’t you go to sleep tommy it’s 2 in the morning?
tommy:why don’t you die you dumbazz