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.
According to Daniel Cassidy in his work of false etymology, How The Irish Invented Slang, the word finagle is Irish. This is strange, because it isn’t used much in Ireland. It is primarily an American slang term which means to cajole or ‘work’ someone or something to obtain some advantage. There is no real agreement about where it comes from, though similar terms are found in English dialects with a similar meaning, such as ‘fainaigue’, which apparently means to take advantage or to shirk work.
Cassidy’s claim is ludicrous. He says that finagle comes from the Irish fionnadh aclaí, which he says means ‘adroit ascertainment.’ The phrase is unknown in Irish, of course. Cassidy had no evidence at all that anyone had ever used it or would ever use it and if we look at the constituent words we can see that it is a very, very poor fit for finagle.
The phrase ‘adroit ascertainment’ is pretty bizarre in itself, but the fact is that this interpretation is made of the most obscure and unlikely meanings of the two words. The word fionnadh has the primary meaning of fur, the secondary meaning of whitening or scorching, and only the tertiary meaning of ascertainment. The word aclaí primarily means fit, then flexible, with adroit only being a tertiary meaning. In other words, an Irish speaker trying to understand what this phrase means would start with ‘fit fur’, move through ‘flexible whitening’ and having exhausted the permutations of ‘flexible fur’ and ‘fit whitening’ or indeed ‘flexible scorching’ and ‘fit scorching’, might just finally arrive at ‘adroit ascertainment.’
In other words, Cassidy’s claim in relation to this word is nonsense.