A lovely retort when someone is acting like a douchebag and a complete idiot - i.e. boob/tit. A very convenient word, and should be included in many college students' vocabularies. It gets to the point, and leaves people shocked as to how to respond.
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).