President Trump speaks at the White House on Nov. 16. (Saul Loeb/AFP/Getty Images (Saul Loeb/AFP/Getty Images)

From the moment he tweeted “covfefe” in the middle of the night, President Trump has been perplexing his millions of Twitter followers with cryptic messages ranging from vague threats to North Korea to his retweets of Islamophobic videos without any comment.

But on Monday, a curious person by the name of Scott Free caught the Internet’s attention.

The unfamiliar proper noun appeared in Trump’s remarkable tweetstorm Monday, in which he wished a long prison sentence on his former personal lawyer Michael Cohen and insisted longtime adviser Roger Stone would not testify against him, leading some to question whether the statements amounted to witness tampering.

“'Michael Cohen asks judge for no Prison Time,'” Trump began. “You mean he can do all of the TERRIBLE, unrelated to Trump, things having to do with fraud, big loans, Taxis, etc., and not serve a long prison term? He makes up stories to get a GREAT & ALREADY reduced deal for himself, and get..... his wife and father-in-law (who has the money?) off Scott Free.”

Aside from whether the tweets amounted to obstruction, there was a second query on everyone’s mind: Who is Scott Free? Some thought he might be a new character in the Russia investigation. Others thought Trump might be referring to a DC Comics superhero named Scott Free, whose alter ego is Mister Miracle.

But, of course, what Trump meant was “scot-free,” a centuries-old phrase meaning to escape punishment, which has nothing to do with a person named Scott. In less than a half-hour, Merriam-Webster reported that online dictionary searches for the definition or spelling of the word had spiked 3,100 percent.

“Scot-free attracted considerably more attention than it usually does on December 3rd, 2018, after President Trump employed the word with an uncommon orthographic form, in a tweet,” the dictionary said, meaning, in plain English, that Trump spelled it weirdly. Scott Free, by contrast, the dictionary said, is just “some guy, probably.”

“In [Trump’s] defense,” Jeremy Butterfield, editor of Fowler’s Dictionary of Modern English Usage, told The Washington Post, “many people do believe the phrase has to do with [the name] Scott.”

People have been assigning wrong origins or spellings to the age-old idiom for years, according to the 2008 book “Common Errors in English Usage” by Paul Brians, a retired English professor at Washington State University. People might think the term has something to do with Scottish people (or an unfortunate “Scott”) or that it is “scotch-free,” somehow related to whisky. Others, Brians noted, have erroneously believed “scot-free” alludes to Dred Scott, the slave who sued for his freedom only to lose in an 1857 Supreme Court case.

But really, scot-free traces its roots back to a medieval tax called a “scot” that arose in the 14th century, according to Merriam-Webster. The Vikings could also be to blame for the origin of the phrase: “Scot” is derived from the Old Norse words “skot” and also “shot” — yes, like shooting a gun or taking your shot. The Gaelic Etymology of Languages of Western Europe, an 1877 dictionary, explains that shot and scot meant the same thing at that time, as in a “contribution that ... is ‘shot’ into the general fund.” Back in those days, if you skirted around the tax, you weren’t Al Capone. You were scot-free.

There were religious scots — Romescots, paid to the papal, and soulscots, paid by a dead person’s family to his church — and there were also party scots, an archaic version of modern-day cover charges at bars. According to Oxford Dictionaries, “scot-ale” referred to the financial contributions that guests were required to make when notable people invited them to their alehouses for festivities. As Katherine Connor Martin of Oxford Dictionaries noted: “It was true in the most literal sense that no one got off scot-free.”

Butterfield noted on his personal linguistics blog that Shakespeare was among the scribes to use “shot-free,” as he did in “Henry IV.” “Though I could 'scape shot-free at London, I fear the shot here,” the character Sir John Falstaff says in Act 5.

Trump’s intended usage Monday, meaning to get away with something without punishment, is just as old. The Oxford English Dictionary records one of its earliest known usages in 1528. On Monday, Merriam-Webster pulled an example from 1542: “Asymbolus, he that commeth to a bankette, without appoyntment, an unboden gest. also he that gothe scot free, and payeth nothing,” as written by Thomas Elyot in Bibliotheca Eliotae Eliotis librarie.

By Tuesday morning, Butterfield had updated his original article on the etymology of “scot-free” to include Trump’s use of it Monday. He calls Trump’s example a “special kind of eponym eggcorn.” In linguistics, an eponym refers to people whose names inspire words (the nonexistent “Scott” here), whereas an eggcorn is a language error when someone’s usage is close but not quite correct — essentially close but no cigar.

It’s derived from the word “acorn.”