foucault, n. A howler, an insane mistake. “I’m afraid I’ve committed an egregious foucault.” (via Norm). Still all a bit of a fuss about Sweet Foucault.
Many thanks to Lenox Napier, who says this has been inflicted on businesses in AlmerÃa since at least the 1970s, and who notes the loving care with which fonts were matched when phone numbers changed from 6 to 9 digits.