A traffic light - otherwise known in other parts of the US as a stop light...
Trustafarian is the portmanteau of the words "trust fund" and "Rastafarian". A trustafarian is typically an upper-middle-class white kid who attends school at Boulder who is wholly funded by his parents (whose fortunes are usually amassed through giant corporations) and talks of the evils of capitalism.
In most parts of the world a sieve is a perforated instrument used to strain liquids, but at UW hockey games at the Kohl Center a sieve is the away team's goalie. After every Wisconsin goal the student section engages in a chant that likens the goalie to an instrument that lets things through its grasp.
The original name for the area now known as Roanoke. "Big Lick" got its name from an exposed portion of salt that drew wildlife to the area.
A nickname for the city of La Crosse itself. La Crosse is Wisconsin's main city on the western edge of the state. Also, it happens to be right up against the Mississippi, which is why many liken it to a coastal town (albeit facetiously).