The red arrow that shows up on some New York traffic lights to let drivers and pedestrians know that vehicles aren't permitted to turn. Considered unsafe for drivers and pedestrians alike because five seconds is hardly enough time for a driver to make a complete stop.
Why can't the DOT make those red arrow signals at least fifteen seconds long?! I hate those New York 5-second warnings!
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).