Susan Walsh / AP

President Trump has added a new epithet to his seemingly endless arsenal of invectives directed at political foes. In a tweet sent early Friday morning, he called former FBI Director James Comey an “untruthful slime ball.”

It was inevitable that Trump would come up with something colorful to sling at Comey, after details from Comey’s new tell-all began leaking on Thursday. In the book, titled A Higher Loyalty: Truth, Lies, and Leadership, Trump is portrayed in an unflattering light. Not only does the former director harshly condemn the president’s leadership, but he also offers blunt physical descriptions at which Trump could take offense. (“His face appeared slightly orange with bright white half-moons under his eyes where I assumed he placed small tanning goggles,” Comey writes of his first meeting with Trump.)

The president has, in the past, leveled all sorts of insults at Comey. Using his favored frame of adjective-plus-name, Trump has called him “leakin’ James Comey,” “sanctimonious James Comey,” and “lying James Comey.” (The Republican National Committee embraced the last insult for its new website, lyincomey.com, launched just in time for the book’s release.) Perhaps the most memorable one came the day after Trump fired Comey, when he told Russian officials visiting the Oval Office that the outgoing director was “crazy, a real nut job.”

Slimeball, however, is a new one for Trump—at least on Twitter. The closest he’s come to using it in the past was back in February 2014. At the time, he called Atlantic staff writer McKay Coppins, then a writer at BuzzFeed, a “slimebag reporter” after Coppins published an article critical of Trump’s political aspirations.

Slimeball and slimebag are members of a larger family of slangy smear words involving slime. Slime originated in Old English about a millennium ago to refer to substances like “soft glutinous mud” and “alluvial ooze,” as the Oxford English Dictionary puts it. By Middle English, slime was used in disparaging references to humans; the same dictionary cites a 14th century poem, “The Pricke of Conscience,” that quotes Saint Bernard on the vileness of humanity: “Man here es nathyng elles bot a foule slyme.”

Lexicographer Jonathon Green, in his authoritative work Green’s Dictionary of Slang, notes that the use of slime for “an extremely unpleasant person” may have been pioneered by Charles Dickens in his novel Martin Chuzzlewit, in which an unsavory relative of the title character is named Chevy Slyme.

But slime epithets didn’t really take off until the late 1960s. In a study of undergraduate students’ use of slang conducted at Brown University in 1967 and 1968, slime is defined as “a small or insignificant person.” Slime compounds were soon to follow. The earliest examples that Green has found for slimeball come from Joseph Wambaugh’s 1972 novel The Blue Knight, about a Los Angeles beat cop. Wambaugh actually used slimeball several times in the book. Here’s a selection:

I’d known from the first day he opened that place it would be a hangout for slimeballs. …

“If you slimeballs could have my job I wouldn’t want it,” I said, let down because it was over. …

“Yeah, I’ve rousted a couple thousand slimeballs in my time.” …

Whether you’re fired for pushing a slimeball down the fire escape, or whether you’re booked for lying in court to put a scumbag where he ought to be … they got to pay you that pension.

Slimebag, along with other compounds like slimebucket and slime-mouth, began popping up as a slur in the 1980s. Meanwhile, –ball also became a productive element for putdowns—think scuzzball. Jonathan Lighter, the author of The Historical Dictionary of American Slang, catalogued the effervescence of –ball epithets in a 1998 piece for The Atlantic:

The disparaging scuzz of the sixties has evolved into the equally disparaging scuzzball of the 1980s and 1990s. As the essayist and novelist Nicholson Baker has noted, the suffix -ball has become an important resource for the slangy smart-alecks of our time. Think of the belittling butterball, cheeseball, cornball, dirtball, goofball, hairball, nutball, oddball, sleazeball, slimeball, and weirdball.

Trump has occasionally used other –ball compounds in his name-calling, as when he dubbed Penn Jillette, the magician and former Celebrity Apprentice contestant, a “goofball atheist” in 2015. But as with the oozy descendants of the Old English slime, there are many more –balls where that came from in American slang—and Trump may someday work his way through all of them.

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