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.
If you look at Douglas Harper’s excellent website, Online Etymology Dictionary, at
https://www.etymonline.com/word/buster, you will find that the word buster apparently first surfaced in the 1830s in the Missouri/Arkansas area. Its original meaning was an exceptional thing or a very strong man and it seems to derive from bust as in break. It also came to mean a spree and the kind of person who would be out on a spree.
Cassidy ignores these facts and inexplicably decides that buster means a fellow, a joker, a roisterer and that it comes from the Irish word pastaire.
According to Ó Dónaill, pastaire means “cheeky fellow; brat”. Of course, there is no evidence linking pastaire with buster, and Cassidy only manages to make a case by changing the meanings so that both words apparently mean ‘trickster’.