Grind

A grind is a playboating move requiring a very specific positioning of a log or metal rail, which the kayaker slides down while facing sideways and balancing. You wont see that very often! This kind of move is much more common in snowboarding, skateboarding and roller-blading.

It can also mean sidesurfing a green wave. Turn perpendicular to the current at the top of the wave and "grind" down it...