Bill Walsh, a Washington Post copy editor who wrote three irreverent books about his craft, noting evolutions and devolutions of language, the indispensability of hyphens and his hostility toward semicolons, and distinctions — for the sake of clarity — between Playboy Playmates and Playboy Bunnies, died March 15 at a hospice center in Arlington, Va. He was 55.

The cause was complications from bile-duct cancer, said his wife, Jacqueline Dupree, a Post informational technology specialist.

In the hurly-burly of a newsroom, where even the best reporters have widely varying degrees of grammatical competence, copy editors are the often unheralded guardians of language and common sense. They are the front-line mud soldiers in an endless war against bad spelling, ill-considered sentence construction and factual errors.

They prevent English teachers everywhere from wincing. They save behinds.

By many accounts, Mr. Walsh stood at the zenith of his profession.

(The Washington Post)

Mary Norris, the recently retired New Yorker magazine copy editor and author of “Between You & Me: Confessions of a Comma Queen,” called Mr. Walsh “that rare thing: a celebrity copy editor . . . clever, decisive, entertaining, and knowledgeable, in person and on the page.”

“Generous and collegial,” she continued in an email, he was “sought after on the copy-editing circuit (and there is one!).”

The publication American Journalism Review once described Mr. Walsh as “the undisputed king of copy bloggers.” He dubbed his long-running editing and grammar website The Slot, after the nickname for the central location the copy chief traditionally occupied in the newsroom. In the era before computers, rank-and-file copy editors sat along the edge, or “rim,” of the copy desk, tossing headlines and stories to the chief in the center, or “slot.”

Among other positions during his 20 years at The Post, Mr. Walsh served as the copy chief of the National and Business desks.

Mr. Walsh wrote three volumes about copy editing, “Lapsing Into a Comma” (2000); “The Elephants of Style” (2004), which punned off William Strunk Jr. and E.B. White’s ubiquitous grammar handbook “The Elements of Style”; and “Yes, I Could Care Less: How to Be a Language Snob Without Being a Jerk” (2013).

Mr. Walsh relished playing the part of a curmudgeon, writing from the perspective of “some past-his-prime newspaper guy . . . yelling at you.”

While holding his ground on proper word choice, capitalization and subject-verb agreement, Mr. Walsh was far less prescriptive than other language mavens regarding split infinitives, sentence fragments, conjunctions at the beginning of a sentence and prepositions at the end. He also gave up trying to annihilate the word “hopefully” as an adverb.

He saw value in Strunk and White’s adages (“omit needless words”) but did not lionize the volume as the infallible word of the grammar gods. He regarded rules as sometimes there to be broken — depending, of course, on the judgment and tolerance of a copy editor.

His books were not aimed at writers of Ivy League graduate theses. They were grounded in workaday newspaper usage: Some company names include exclamation points that are not generally used in print, as “it risks sounding way too excited in headlines (Tech Stock Surge Boosts Yahoo!).”

A copy editor must at all times exercise vigilance in word choice, he cautioned. A Playboy Bunny is a Playboy Club waitress who has donned a cottontail uniform, he explained, while a Playmate is a centerfold. (The term “Playboy model” should be used gingerly, he wrote, as it could refer to women with the modeling arm of Hugh Hefner’s enterprise, in addition to those who doff their clothing for the magazine.)

He rolled his eyes at silly redundancies (“Armed gunmen: They’re the worst kind”) and explained the utility, for a copy editor, of being well read. “Although the people of Pakistan are Pakistanis, the people of Afghanistan are Afghans,” he wrote in “The Elephants of Style.” “The word afghani refers solely to the country’s main unit of currency. To call an Afghan an afghani is like calling an American a dollar.”

Mr. Walsh said he tried to steer clear of absolutes in language, but he had his peeves. “The semicolon is an ugly bastard,” he wrote in “Lapsing Into a Comma,” “and thus I try to avoid it.”

The hyphen, however, he found beautiful — an instrument of clarity and precision.

“Most people don’t understand hyphens, so they lash out against them,” he told American Journalism Review. “I’m a big advocate of the hyphen. If you write ‘the orange juice salesman,’ you have a salesman who’s orange. The orange-juice salesman is more precise.”

William Francis Walsh was born in Pottsville, Pa., on Dec. 20, 1961, and completed high school in the Phoenix suburb of Mesa, Ariz. He was a 1984 journalism graduate of the University of Arizona.

He worked at the now-defunct Phoenix Gazette and the Washington Times before joining The Post.

In 2000, he married Dupree. Besides his wife, of Washington, survivors include his mother and stepfather, Molly Chilinski and Gary Chilinski of Eloy, Ariz.; two brothers, Terence Walsh of Frederick, Md., and Kenneth Walsh of New York City, both copy editors; and a sister, Jennifer Jaurigue of Chandler, Ariz.

Mr. Walsh was a frequent presenter at conferences of the American Copy Editors Society, and in 2016 he was a keynote speaker at a gathering of the Editors Association of Canada.

The New Yorker’s Norris, the other keynote presenter, recalled that Mr. Walsh “was addressing some nitpicking thing like whether or not to continue to capitalize ‘the Internet.’ The hard-liners still capitalize it (and make two words of ‘Web site,’ with the cap), although the future is clear. The kids will lower-case it, because [and this is pure Bill] what don’t they lower-case? He held out hope for them, though. He showed a slide of a beach chair and a cocktail, the implication being that once we retire — or go to our reward — they can do what they want.”