Inserting your hand, in a fish-shaped pattern, in-between someone's thighs and rapidly slapping the inner thighs back and forth.
Getting "Sea-Bass'd" is when one individual, of genuine demeanor, approaches another individual and suddenly stops and stares at the second individual until the approached party becomes concerned and raises the alarm. Usually, this will consist of hailing the approaching party with a typical social response, e.g. "Hey", "Hello?", "what's up Man/Girl?", or perhaps if the two parties involved are not on familiar terms (which makes the sea bassing epic) "May I help you Sir/Ma'am?". At this point the party conducting the Sea Bassing quickly lowers their posture and inserts their hand, flat and erect, in-between the target's legs and slaps the inner thighs with their hand over and over again, mimicking a live fish that has, somehow, found its self outside it natural habitat and within the domain of a strange land-creature's legs. This should be continued until the approached party has retreated. If done correctly, the initiating party may exclaim: "You've just been Sea-Bassed". This is an example of a "Front-Bassing", the most difficult Sea-Bassing to accomplish since the target is fully aware of your intentions for strange activity.
by Hot-Tuna May 14, 2013