bogus

First attested as an underworld term for an apparatus for creating counterfeit coins, then the coins themselves. Later, the word was applied to anything of poor quality. The newest use to mean useless is probably from the slang of computer hackers. The origin is unknown, but there are at least two theories that try to trace its origin: * From Hausa boko (“to fake”). Since bogus first appeared in the United States, it may be possible that its ancestor was brought there on a slave ship. * From criminal slang as a short form of tantrabogus, a 19th-century slang term for a menacing object, making some believe that bogus might be linked to bogy or bogey (see bogeyman).

出典: Wiktionary「bogus」（CC BY-SA 4.0）