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.
The term muttonhead was used by the beginning of the 19th century to mean a stupid person. By the early twentieth century mutt and muttonhead were used in America of non-purebred dogs, probably because the rough and untidy coat would not be like the coat of a purebred.
Daniel Cassidy, in his etymological hoax, How The Irish Invented Slang, says that mutt comes from madadh or madra (mada in Dinneen) the Irish for dog (not mongrel.) These words begin with m but apart from that, they don’t sound much like mutt.
Cassidy’s definition of the word madra or madadh is typically dishonest. He says that it means ‘a dog, esp. an inferior breed, a cur, a mutt’. This definition emphasises the link with mutts and mongrels. In reality, madadh or madra is simply the Irish word for dog. It is not especially associated with mutts or mongrels or bad breeding. Indeed, a pure-bred dog in Irish is a madra folaíochta!
Mutt is an American expression for a mongrel dog. According to the dictionaries, the term mutt is thought to be a version of muttonhead, which enters English around the same time (beginning of the twentieth century) and means a fool or a dolt. There is no great mystery about this. Muttonhead is saying that something or someone resembles a sheep and mutt is used of people as well as dogs from the start. Of a person, this probably means they’re stupid. Of a dog, it probably just means that they have a shaggy and unkempt coat.
Daniel Cassidy, the Great Fraud, says that mutt doesn’t come from muttonhead. According to him, it comes from madadh or madra (mada in Dinneen) the Irish for dog (not mongrel.) These words begin with m but apart from that, they don’t sound much like mutt.
However, the funniest thing in this piece is the way that Cassidy tries to rubbish the derivation from muttonhead.
“Some Anglo-American lexicographers derive mutt from muttonhead, as in a sheep’s head. But a muttonhead is a dunderhead or a dolt. Most mutts are (street) smart.”
Well, that proves it then! Hearken to his cold, inexorable logic …