Philip French’s review of the film of the The Da Vinci Code film in the Observer in April 2006 contained several neat put-downs, such as “Brown’s novel is called a ‘page-turner’, partly because no one capable of reading without moving their lips would wish to linger over his prose”, and “The cryptographers are constantly creeping into crypts, talking crap and copping out”. He described the Robert Langdon character as “professor of religious symbology (a branch of codology) at Harvard”.
That sounds like simple exposition, unless you know that codology has nothing to do with code-breaking. It’s actually an Irish colloquial term, explained by H V Morton in 1930 in this way: “There is in Ireland a science unknown to us in England called codology. Nearly every true Irishman is either a graduate or a professor. The American for codology is ‘bunk’, or perhaps ‘bla’; the English is ‘leg-pulling’. There is nothing your true Irishman likes better than putting over a tall story on an Englishman.” Americans may argue that the more recent kidology is a better fit.
Codology derives from the slightly older slang term cod, meaning a joke, a hoax, a parody, or take-off. The Belfast Newsletter used it in November 2003: “Seems like politics is a chip off the old block for this candidate who assures us he will not engage in any codology on this campaign.”