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.
Cassidy explains this term as deriving from Irish (of course).
Jazzbo, Jasbo, Jazz–bo, n., (someone or something) infused with great heat, passion, enthusiasm, high spirits, and excitement. Vaudeville slang for wild physical comedy, exuberant slapstick, hokum.
Teasbach, teaspach (pron. j’asbah, ch’asbah, t’aspǝ), n., (of person) animal spirits, exuberance; heat, liveliness, ardour, passion, sultriness; heat of the blood; wantonness; (of horse) spiritedness, tendency to cavort; (of cattle) tendency to gad about.
In reality, jazzbo first makes its appearance shortly after the word jazz itself, just before the 1st World War. It initially referred to slapstick comedy in Vaudeville, then to black vaudeville performers, and then to syncopated music. Some scholars link it to a certain Jasper ‘Jasbo’ Brown, who was a musician. Others have claimed that it originated in New Orleans with the phrase chasse beau. There doesn’t seem to be much evidence in support of the latter.
Wherever it comes from, I am sure it has nothing to do with teaspach (pronounced chaspah – Cassidy knew nothing about Irish pronunciation), which is the Irish for a heatwave or hot spell of weather (a definition that Cassidy ignores in favour of the ones he thinks fit better with jazzbo). You can find a proper and honest definition of the meanings of teaspach here: https://www.teanglann.ie/en/fgb/teaspach