Etymology From Middle English thudden (“to strike with a weapon”), from Old English þyddan (“to strike, press, thrust”), from Proto-Germanic *þuddijaną, *þiudijaną (“to strike, thrust”), from Proto-Germanic *þūhaną, *þeuhaną (“to press”), from Proto-Indo-European *tūk- (“to beat”). Cognate with Old English þoddettan (“to strike, push, batter”), Old English þȳdan (“to strike, stab, thrust, press”), Old English þēowan (“to press”), Albanian thundër (“a hoof, talon, a shaft", figuratively, "oppression, torment”).
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The sound of a dull impact.
These were but the thoughts of a second, but the voices were nearer, and I heard a dull thud far up the passage, and knew that a man had jumped down from the churchyard into the hole.1898, J. Meade Falkner, chapter 3, in Moonfleet (fiction), London: Edward Arnold:
Ramos had locked Salah’s right arm and turned him, judo-style, as they lost balance going for the same ball. Television replays hardened the suspicion it was a calculated move on Ramos’s part and, when Salah landed with a hell of a thud, the damage was considerable.2018 May 26, Daniel Taylor, “Liverpool go through after Mohamed Salah stops Manchester City fightback”, in The Guardian, London, →OCLC, archived from the original on 27 May 2018:
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A hard, dull impact.
Sinclair told the B.A.R. [Bay Area Reporter] he felt the thud of the pistol on his left cheek about a 100 feet from his car, […]1995 January 26, Mary Ann Swissler, “Fremont Man Recovering from Livermore Pass Attack”, in Bay Area Reporter, volume XXV, number 4, San Fransico, page 18:
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BDSM, Lifestyle, Sexuality A slower, dull impact with a wide surface area.
Pillowcase whippings offer the look and feel of a flagellatio scene’s atmosphere, mood, and psychology while involving only very mild amounts of pain. (A pillowcase is almost all “thud” and very little “sting” in the sensations it creates.)1992, Jay J. Wiseman, SM 101: A Realistic Introduction, 2nd edition, San Francisco: Greenery Press, published 1996, →ISBN, page 181:
It still wasn’t what I’d call painful but as he swung his arm and the strands of the flogger hit me together it felt like a solid thud rather than a number of different tails stinging me.2013, Sophie Morgan, No Ordinary Love Story, London: Penguin Books, →ISBN, page 294:
Etymology From Middle English thudden (“to strike with a weapon”), from Old English þyddan (“to strike, press, thrust”), from Proto-Germanic *þuddijaną, *þiudijaną (“to strike, thrust”), from Proto-Germanic *þūhaną, *þeuhaną (“to press”), from Proto-Indo-European *tūk- (“to beat”). Cognate with Old English þoddettan (“to strike, push, batter”), Old English þȳdan (“to strike, stab, thrust, press”), Old English þēowan (“to press”), Albanian thundër (“a hoof, talon, a shaft", figuratively, "oppression, torment”).
1
To make the sound of a dull impact.
At the same instant two arrows thudded into the carcass of the deer over which he knelt, passing but a few inches from his head.1849, George Frederick Ruxton, Life in the Far West (non-fiction), New York: Harper & Brothers, page 183:
[…] while the tears streamed from his eyes, and his tail waved and thudded in perfect time on the sanded floor. But for the said thudding of the tail, I would have stopped, fancying the poor animal's nerves had been set on edge.1874, Mrs George Cupples, “Mrs Glen and the Aberfoyle Orphanage”, in The Poetical Remains of William Glen, Edinburgh: William Paterson, page 47:
The aircraft with the most threatening mission and highest loss rate was the F-105 Thunderchief. Of 833 "Thuds" built, 382 were lost between 1965-1972.2002, US Naval Academy Class of 1954, 2nd edition:
The F-105 Thunderchief was already the air force's workhorse in Vietnam, flying three-quarters of Rolling Thunder sorties and suffering the highest casualties. […] We do know Thuds were very fast, could take a beating, and packed a big punch.2014, John McCain, Mark Salter, Thirteen Soldiers: A Personal History of Americans at War, page 255: