I have the old English major’s habit of never reading past a word I don’t know, and have worn out more than a few pocket dictionaries. There are certain kinds of books, generally high-toned novels, that you expect to give you a good lexical workout—Ford Madox Ford’s Parade’s End, for example, which I read for the first time this year after watching the great HBO miniseries, or anything by William Faulkner.

Military history is not in this category. Accounts of battle have their own ways of confusing readers (troop movements and tactics, geographical fine points, jargon and acronyms), but they rarely display recondite vocabulary, which is why I was surprised by how many times Rick Atkinson, in his superb World War II Liberation Trilogy, stopped me cold.

Here are some of the puzzlers in The Guns at Last Light, the trilogy’s final volume: bedizened, biffing, cozenage, bootless, jinking, maledictory, spavined, tintinnabulation, anabasis, flinders. Some in that list may be more familiar than others, but speaking as someone who has been reading and writing for four decades, if a word stops me, it’s going to stop most people.

Google Books’ Ngram Viewer, which charts how frequently a word or phrase appears in a sample of roughly 5.2 million books and 500 billion words, confirms the obscurity of these specimens. An Ngram score shows what percentage of the sample’s word count a particular word or phrase represents over a particular period of time. Take gutful, which makes up .0000005 percent of Ngram’s English-language sample from 2008 (when Last Light was published), as opposed to brave, its equivalent, which has a score of .001. Gutful is used three times in Last Light (pages 53, 167, and 346), which means that the author thrice chose a word 2,000 times less common than its perfectly suitable synonym.

Atkinson is an old newspaperman, as I am. In newsrooms there is little patience for the use of a difficult word where a simpler one will do. “Good prose is like a windowpane,” wrote George Orwell in his famous essay “Why I Write,” a rule that would seem to counsel against ever stopping a reader with an unfamiliar word. It’s good advice for beginners, but serious readers are also lovers of language. I find that the occasional obscure word, used correctly, spices prose.

“To be honest, I have never thought about it,” Atkinson told me, though he confessed to chafing at newspaper norms. He has a master’s degree in English language and literature, and said that he “feels no obligation to avoid sending a reader to the dictionary,” provided that the word in question is exactly the right one. Atkinson read a lot of British histories and memoirs in researching The Guns at Last Light, and was both infected and enchanted by British expressions. Biffing, a goofy word that just oozes Anglo slapstick, comes straight from the novelist Evelyn Waugh, who served as an officer in the Royal Marines during World War II.

“When I wrote flinders, I suppose I could have used splinters,” Atkinson told me. “But to me, flinders is so much more vivid. Even if it is obscure, in description one can intuit what it means; it means exactly what it sounds like it means.” The same goes for jinking, a word he picked up from American fighter pilots who described their aerial maneuvers to him.

For all his love of arcane words, Atkinson said he hates crossword puzzles and word games. “My wife and children whip me at Words With Friends every time.”