Also known as a flagperson, one who wears brightly coloured work clothes and directs traffic. Usually carries a handheld traffic control sign with "stop" and "slow" written on either side. Most often seen around construction zones to ensure vehicle and pedestrian traffic flows safely past the work area.
"Hey, that traffic troll let everyone else through but made me stop!";
"We can't get down that road, traffic trolls are blocking it while they fill some potholes."
Someone who does provocative things like texting, talking, checking facebook, etc. on their cell phones while driving, completely disregarding the safety of everyone else.
That traffic troll I saw at the red stop got into a car crash because he was focusing too much on his texting.