mainly Australian a shed or hut in the bush or a garden
From POTUS To FLOTUS: A Full (White) House Of AcronymsThe faster we move, the more abbreviations and assorted acronyms we use, and when it comes to talking about the folks who reside at 1600 Pennsylvania Avenue—otherwise known as the White House—there are plenty of acronyms to choose from.
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Examples from the Web for bush house
Hallo, they've got to Tubarigan's, the chief's bush-house, and fired it!A Modern Buccaneer|Rolf Boldrewood