Definition of "arch"

[He] spoke his request with so arch a leer.

1710 July 15 (Gregorian calendar), Isaac Bickerstaff [et al., pseudonyms; Richard Steele et al.], “Tuesday, July 4, 1710”, in The Tatler, number 193; republished in [Richard Steele], editor, The Tatler, […], London stereotype edition, volume III, London: I. Walker and Co.; […], 1822

I was every day furniſhing the Court with ſome ridiculous Story; and Glumdalclitch, although ſhe loved me to Exceſs, yet was arch enough to inform the Queen, whenever I committed any Folly that ſhe thought would be diverting to her Majeſty.

1726 October 28, [Jonathan Swift], “Several Adventures that Happened to the Author. […]”, in Travels into Several Remote Nations of the World. […] [Gulliver’s Travels], volume I, London: […] Benj[amin] Motte, […], part II (A Voyage to Brobdingnag), page 247

“Oh!” cried Mrs. Green, with an arch laugh, “you are acquainted with Monsieur Margot, then?”

1828, [Edward Bulwer-Lytton], chapter XVI, in Pelham; or, The Adventures of a Gentleman. […], volume I, London: Henry Colburn, […], page 112

Blanche’s grey eyes gazed at Foker with such an arch twinkle that both of them burst out laughing […]

1848 November – 1850 December, William Makepeace Thackeray, chapter 46, in The History of Pendennis. […], volumes (please specify |volume=I or II), London: Bradbury and Evans, […], published 1849–1850

A certain melancholy that touched her countenance must have been of recent birth, for it had not yet altered the fine and youthful contours of her cheek, nor subdued the arch though resolute curve of her lips.

1906, O. Henry, By Courier

Lassiter ended there with dry humor, yet behind that was meaning. Jane blushed and made arch eyes at him.

1912 January, Zane Grey, chapter 3, in Riders of the Purple Sage […], New York, N.Y., London: Harper & Brothers Publishers

When you're watching a Wes Anderson film, you know it. Within seconds, you spot the symmetrical compositions, the horizontal camera moves, the blocks of garish colour, the san-serif lettering, the arch, wordy, vaguely melancholy humour and all the other elements that distinguish his comedies from everyone else's.

2021 July 12, Nicholas Barber, “The French Dispatch: Four stars for Wes Anderson's latest”, in BBC‎

Ms. Brier specializes in point of view, or P.O.V., videos that confront relatable, often hateable characters, with a subtle sneer, gleefully rubbery body and arch delivery of generational catchphrases like “slay, queen” and “I got you,” often repeated for effect.

2023 March 14, Alexandra Jacobs, “Your Annoying Roommate Is Slaying on TikTok”, in The New York Times‎

the most arch act of piteous massacre

c. 1593 (date written), William Shakespeare, “The Tragedy of Richard the Third: […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act IV, scene iii]

Challenger the super scientist, Challenger the arch-pioneer, Challenger the first man of all men whom Mother Earth had been compelled to recognize.

1929, Sir Arthur Conan Doyle, When the World Screamed‎

My worthy arch and patron comes to-night.

c. 1593 (date written), William Shakespeare, “The Tragedy of Richard the Third: […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act IV, scene iii]