From Longman Dictionary of Contemporary Englishgo walkaboutgo walkaboutspokenDISAPPEAR to get lost – used humorously My watch has gone walkabout again. → walkabout
Examples from the Corpus
go walkabout• You know that when a black fella dies the whole family moves out of the house and goes walkabout.• Prunella was right - why the fuss just because Blythe had gone walkabout?• I thought I'd just go walkabout and see what I can dig up.• Our man's gone walkabout for reasons of his own. 