The word “shyster” is one of the most objectionable words around to denote a lawyer. There are others, to be sure—as I’ve documented in Garner’s Dictionary of Legal Usage [3d ed. 2011], in an entry titled “Lawyers, Derogatory Names for”—but shyster is exceedingly pejorative. For many years, its derivation has seemed uncertain. Whenever that happens with a colorful word, fanciful etymologies inevitably crop up.Speculative theories haven’t been in short supply. The Oxford English Dictionary records shyster as being “of obscure origin,” but it ventures the idea that the word might be related to the word “shy” in the obscure sense “disreputable.” That’s a wild guess. Some have suggested that it’s associated with the character Shylock in Shakespeare’s The Merchant of Venice (circa 1599) and that it therefore has anti-Semitic associations. A 1974 book on negotiations conjectures that its origins lie with a disreputable 19th-century Philadelphia lawyer named Schuster; other sources spelled it Scheuster. This eponymic theory has now been debunked. Still another false hypothesis is that it comes from the Gaelic siostair, meaning “barrator”—or one who incites frivolous litigation. Those are only a few of the more than 12 suggestions that have been posited in print.My entry in Black’s Law Dictionary (11th ed. 2019) reads this way: “shyster. (1843) A person (esp. a lawyer) whose business affairs are unscrupulous, deceitful, or unethical; a lawyer without professional honor” (p. 1660). In my legal-usage dictionary, from a different publisher, I define shyster as meaning “a rascally lawyer; one that is shrewdly dishonest” (p. 821). And in the latter book, I observe that the etymological puzzle was conclusively solved in a 124-page monograph written in 1982 by Gerald L. Cohen. He found the solution in previously overlooked material in New York newspapers from 1843 and 1844. Cohen showed that shyster arose as part of an editor’s crusade against legal and political corruption. The correct source word was scatological: the German Scheiss, meaning “excrement.” A Scheisser was a defecator.The 19th-century editor’s name was Mike Walsh, and he was attempting to transcribe the speech of a lawyer named Cornelius Terhune, who was describing what he took to be lowlife competitors at the bar. The “t” in shyster probably got added by Walsh on the analogy of other English words ending in “‑ster,” such as huckster, prankster, punster, trickster, and youngster.The word took hold. It’s even been the subject of litigation. In 1923, the Montana Supreme Court held that shyster, when applied to a lawyer along with imputations that the lawyer had engaged in grossly criminal, anarchistic, and unprofessional conduct, was libelous per se. The word exposed the lawyer to “hatred, contempt, ridicule, and obloquy, causing him to be shunned and avoided, and tending to injure him in his business,” the court said.In a 1940 case, the U.S. Court of Appeals for the 5th Circuit wrote, in dictum, that a lawyer who advertises and gives advice without actually seeing his client would certainly be considered a shyster.Six years later, the Nebraska Supreme Court defined shyster as “a pettifogger, one who carries on legal business in a dishonest way, one without professional honor.”So the word is no joke.In 1993, Judge Frank Easterbrook of the U.S. Court of Appeals for the 7th Circuit suggested, through circumlocution, that some lawyers before him might deserve the epithet. He wrote: “Appellants have other arguments, but displaying them would do little more than illustrate why some members of the public believe that ‘shyster’ and ‘lawyer’ are synonyms. This is a frivolous, doomed, and sanctionable appeal.” To say that it’s sanctionable isn’t to say that it’s allowable; Judge Easterbrook was suggesting that the lawyers should be fined.Today, the excrementitious associations of the word have been long forgotten, even though the word continues to carry odium and opprobrium.By the 1940s, the exclusive association with lawyers had also worn off. Hence the word came to denote dishonorable people in all callings—immoral people in business, religion, and education as well. When that happened, the disambiguating phrase “shyster lawyer” came into being, first appearing about 1900 and reaching the height of its popularity in the 1940s. By that time, any sense of redundancy had been forgotten.The 1982 Cohen monograph may have solved the mystery, but the popular imaginings continue. People won’t stop their whimsical theorizing about the word’s history. They’re not scholars. They’re etymological shysters.