A car's turning signal. Cars sold in New England may as well have these as optional instead of standard, because few people use them.
That guy decided to turn on his left blinka after he had been sitting in the middle of the road while the traffic behind him stood dumbfounded for about half a minute.
Rhode Island/Massachusetts slang for a Blinker, a.k.a. turn signal.
That Masshole didn't use his blinka on that turn.