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 is his book How The Irish Invented Slang, the slang expression ‘a nail’ means a dose of venereal disease. If this is the case, it seems likely to me that it refers to the inflammation and swelling that someone would experience when they catch themselves on a nail, though this is only a guess.
Cassidy claimed that it comes from ainfheoil, an Irish and Scottish Gaelic word deriving from the elements feoil (meat, flesh) and ain-, a prefix that means unnatural or bad. It is worth quoting Cassidy’s definition:
Ainfheoil [pron. An’ól, an⁓ĭӱ-il] n., corrupt flesh, gross flesh, granulations; fig. STD. (Dineen, 19; Dwelly, 15.)
This is very inaccurate. Dinneen defines this word as meaning ‘proud flesh, gross flesh’. Dwelly, which is a dictionary of Scottish Gaelic, also defines it as ‘proud flesh, gross flesh’. Proud flesh is the primary meaning of this word. Proud flesh is a specific phenomenon, a kind of tissue that grows around a wound when it is not fully healed. Cassidy’s ‘figurative’ meaning of sexually transmitted disease is imaginary.
The ‘phonetics’ given by Cassidy are also imaginary. The n’ is a convention in Irish phonology to show a palatal consonant, but the rest is false. A correct phonetic transcription would be something like /an̠ʲɔːlʲ/.