Derived from various word games, its a word that sounds real enough. But is actually a made up word worth a lot of points in scrabble.
Also used by idiots who try to sound clever, such as W13
"Due to unprotensenzelous reasons, Off Topicforum is now closed."
The use of the word "blue" to refer to sexually explicit content was first recorded in Scotland in 1824. "Blue" meant "lewd" because prostitutes dressed in blue gowns.