an·​te·​di·​lu·​vi·​an | \ ˌan-ti-də-ˈlü-vē-ən How to pronounce antediluvian (audio) , -(ˌ)dī- \

Definition of antediluvian

1 : of or relating to the period before the flood described in the Bible
2a : made, evolved, or developed a long time ago an antediluvian automobile that antediluvian relic known as a slide rule
b : extremely primitive or outmoded an antediluvian prejudice antediluvian in his politics

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Other Words from antediluvian

antediluvian noun

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Did You Know?

Before there was "antediluvian," there were the Latin words ante (meaning "before") and "diluvium" (meaning "flood"). As long ago as 1646, English speakers were using "antediluvian" to describe conditions they believed existed before the great flood described in the biblical account of Noah and the ark. By the early 1700s, the word had come to be used as both an adjective and a noun referring to anything or anyone prodigiously old. Charles Darwin used it to characterize the mighty "antediluvian trees" some prehistoric mammals might have used as a food source, and in his American Notes, Charles Dickens described an elderly lady who informed him, "It is an extremely proud and pleasant thing . . . to be an antediluvian."

Examples of antediluvian in a Sentence

He has antediluvian notions about the role of women in the workplace. found evidence in the Middle East of an antediluvian people previously unknown to history
Recent Examples on the Web One stop could be Nederland’s antediluvian Goldminer Hotel, listed in the Registrar of Historic Places. New York Times, "Leaf Peeping Is Not Canceled: 6 Drives and Hikes to Try This Fall," 1 Oct. 2020 Yet this paragon was managed according to an antediluvian five-volume set of rules. Geoff Colvin, Fortune, "For a time, Jack Welch was the most valuable CEO on earth," 2 Mar. 2020 At worst, Muslims were castigated as a community with antediluvian beliefs. Sharik Laliwala, Quartz India, "Facing bias, India’s Muslims are rallying behind its secular constitution, not radical Islam," 20 Feb. 2020 By mastering antediluvian musical syntax, the Ramblers accorded the old-time string band canon great respect while also equipping themselves to reimagine it with their own exuberant stamp. Bill Friskics-warren, New York Times, "John Cohen, Champion of Old-Time Music, Is Dead at 87," 17 Sep. 2019 What’s clear here is that the National Right to Work foundation is pushing their antediluvian, anti-worker agenda at all cost at a time when Americans keep demanding stronger laws to protect their right to join together in unions., "A religious discrimination lawsuit filed last month in federal court against a local union and Boston College is being hailed by anti-union groups for upholding individual workers’ rights — and railed against by union advocates who say it’s an attempt to weaken organized labor.," 5 Dec. 2019 The stories were later re-edited to delete such antediluvian tropes, but in the process they were made shorter as well; much of Wirt Benson’s mellifluous prose tumbled to the cutting-room floor. Michael Callahan, Marie Claire, "The Timely Return of Nancy Drew," 9 Oct. 2019 Power was, in this antediluvian period, a voice of piercing moral clarity. Washington Post, "Can an uncompromising activist keep her integrity while working in the White House?," 6 Sep. 2019 Presented as some kind of antediluvian free state for kids, in which play is loosely organized but otherwise unfettered, its conventions are sneakily conservative. Mac Schwerin, Vox, "The case against summer camp," 16 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antediluvian.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of antediluvian

1646, in the meaning defined at sense 1

History and Etymology for antediluvian

ante- + Latin diluvium flood — more at deluge

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The first known use of antediluvian was in 1646

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Cite this Entry

“Antediluvian.” Dictionary, Merriam-Webster, Accessed 25 Jan. 2021.

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English Language Learners Definition of antediluvian

formal : very old or old-fashioned

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