noun. A hard-to-find land, somewhere near Lower Buttmunchistan.
Real citation: "@Garfene I buy a newspaper to read news. Not to look at pretty ads or what's happening under-a-rock-istan. Separate the sections man! :P"
(Jan. 27, 2010, Sean A.J. Bennett, Twitter, http://twitter.com/dacoolkidsean/statuses/8308312820)
Made-up citation: "Be good, kids. Otherwise, your mom will send you to Under-a-rock-istan, where smurfs will set you on fire."