It's a curious thing. It's obviously a portmanteau word of "British" and "Exit" (and that exit would be from the European Union). And, unless someone on the "Let's stay in" side stands up and tells the Brits why that would be a good idea, the very real possibility exists that Britain will leave the EU.
It's not been well-thought about though, by anyone.
If we left, what would happen to all the non-British EU citizens currently working in the UK (around 1.9 million people), or Brits in Europe (around 1 million people)?
How long would it take to "de-treaty" and undo all the legal links that we currently have with Europe? Estimates vary between 7 and 10 years. What would happen to the stock market during that time?
What would happen to the UK's standing in the world? At the moment we project "soft power" by having a seat at most of the major world organisations, We'd be giving up a substantial area of influence straight away, would the others follow suit?
Most importantly, my trips over the channel to eat well in French restaurants, buy cheap red wine and sample a completely different culture for a few days would be badly hit. Has anyone thought about that?