[very common; always pronounced as if capitalized. Orig. fr. the 1930 Sellar & Yeatman parody of British history 1066 And All That, but well-established among hackers in the U.S. as well.] Something that can't possibly result in improvement of the subject. This term is always capitalized, as in “Replacing all of the DSL links with bicycle couriers would be a Bad Thing”. Oppose Good Thing. British correspondents confirm that Bad Thing and Good Thing (and prob. therefore Right Thing and Wrong Thing) come from the book referenced in the etymology, which discusses rulers who were Good Kings but Bad Things. This has apparently created a mainstream idiom on the British side of the pond. It is very common among American hackers, but not in mainstream usage in the U.S. Compare Bad and Wrong.