For some time now, some of my on-line friends have advised me to provide a version of CassidySlangScam without the invective aimed at Cassidy and his supporters. In response to that advice, I am working on providing a glossary of the terms in Cassidy’s ludicrous book How The Irish Invented Slang with a short, simple and business-like explanation of why Cassidy’s version is wrong.
Among the many claims made by Daniel Cassidy in his book, How The Irish Invented Slang, is one which is a real doozy, the claim that doozer comes from Irish duaiseoir, meaning a prizewinner, while the slightly different alternative version, doozie, apparently comes from the adjectival version duaiseach. If you don’t know any Irish, this sounds like a perfectly reasonable claim.
Both these Irish words are given in dictionaries. They are both derived from duais, the primary meaning of which is prize or award. However, duaiseoir was probably invented in the mid-twentieth century as the equivalent of English prizewinner. There is no evidence it existed before it appeared in Ó Dónaill’s dictionary in the 1970s. As for duaiseach, this is an adjective, not a noun (Cassidy conveniently gives its primary meaning as ‘a gift’, but this is his own invention – it is not supported by the dictionaries.)
Where does ‘It’s a doozie’ really come from? You can find a genuine and honest discussion of its origins here: http://www.worldwidewords.org/qa/qa-doo2.htm.