They call it a "furlough".
No, I don't work for the government ... although, if I did, I'd at least have the reassurance that my employer would eventually call me back to work. (Just one more reason why people want to be American civil servants — you really have to be a total screw-up to lose a government job.)
By "furlough" my employer means a temporary layoff, which could last anywhere from a couple of weeks to six months. If they don't fold their tent. Ain't the public sector wonderful?
Of course, according to the most recent data from the Economic Research Department, Federal Bank of St. Louis, the average length of unemployment is 35.4 weeks, or just over 8 months (Link: http://research.stlouisfed.org/fred2, data set UEMPMEAN.) So it could be a while.