Having sex and dancing at the same time. Derived from sexual mating practices of grunion. Grunion are known for their very unusual mating ritual. At very high tides the females come up on sandy beaches and dig their tails into the sand to lay their eggs. A male then wraps himself around the female to deposit his sperm. For the next ten days the grunion eggs remain hidden in the sand, but at the next set of high tides the eggs hatch and the young grunion are washed out to sea
I was gruning all night at prom with my date.
by Grunin July 10, 2008