<humour> A hypothetical bug predicted to exist based on a small number of possibly related event log entries and vague anecdotal user reports. The Higgs Bugson is difficult to reproduce because you don't really know if it's there, and if it is there what is causing it. To find one you will need a Large Hadron Debugger.
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Nearby terms: Hierarchical Object Oriented Design « hierarchical routing « hierarchy « Higgs Bugson » high bit » High bit-rate Digital Subscriber Line » high colour