mas·​to·​don | \ ˈma-stə-ˌdän How to pronounce mastodon (audio) , -dən\

Definition of mastodon

1 : any of various extinct mammals (genus Mammut synonym Mastodon) of the elephant family existing from the Miocene through the Pleistocene that are distinguished from the related mammoths chiefly by molar teeth with cone-shaped cusps
2 : one that is unusually large

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Other Words from mastodon

mastodonic \ ˌma-​stə-​ˈdä-​nik How to pronounce mastodonic (audio) \ adjective
mastodont \ ˈma-​stə-​ˌdänt How to pronounce mastodont (audio) \ adjective or noun

Examples of mastodon in a Sentence

mom-and-pop stores just can't compete with these mastodons of retailing

Recent Examples on the Web

By around 13,000 years ago, our ancestors were on every continent, sharing the Ice Age-era Earth with megafauna like the mastodon. Rachael Lallensack, Smithsonian, "Here Are 12 Things You Might Miss in the Smithsonian’s New Fossil Hall," 7 June 2019 One problem in determining who exactly killed that mastodon rests on finding the bones of the group that did it. John Wenz, Popular Mechanics, "Jaw-Dropping Study Says Some Human Relative Was in California 130,000 Years Ago," 26 Apr. 2017 Defined by the long trunks and massive size, Proboscidea's ancestry include the mastodon of Ice Age fame. David Grossman, Popular Mechanics, "It Will Take Millions of Years for Evolution to Replace What We Might Lose in the Next 50," 16 Oct. 2018 On a much smaller scale, the city’s residents fumed—Hosack prominent among them—when a mastodon fossil excavated in the Hudson Valley was spirited across state lines for the glory of that rival city, Philadelphia. Penelope Rowlands, WSJ, "‘American Eden’ Review: The Ambitious Dr. Hosack," 1 June 2018 Mammoths and mastodons, for example, likely had a two-year gestation period, akin to modern elephants, and would have typically produced just one offspring at a time. Jason G. Goldman, Scientific American, "In 200 Years Cows May Be the Biggest Land Mammals on the Planet," 20 Apr. 2018 Boys dig up prehistoric mastodon fossil in Mississippi. Fox News, "FOX NEWS FIRST: Trump mulls sending National Guard to U.S.-Mexico border; Suspected shooter had feud with YouTube," 4 Apr. 2018 Two months later, a work crew uncovered a massive mastodon skull buried in the ground. Steve Lord, Aurora Beacon-News, "Mastodon model approved for Aurora exhibit at Phillips Park," 3 Mar. 2018 At the on-site archaeological museum of the same name, bone up on the 12,000-year-old history of Illinois River Valley denizens, from Ice Age nomads who hunted huge mastodons to tribal groups that left Illinois in the 19th century. Lori Rackl,, "Bicentennial bucket list," 19 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mastodon.' 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 mastodon

1811, in the meaning defined at sense 1

History and Etymology for mastodon

borrowed from New Latin Mastodont-, Mastodon, genus name, Latinization of French mastodonte, vernacular name for the animal, from Greek mastós "breast, nipple" (probably from a pre-Greek substratal language) + French -odonte -odont; so named from the nipple-like cusps on the crowns of the molar teeth

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15 Jun 2019

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Time Traveler for mastodon

The first known use of mastodon was in 1811

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English Language Learners Definition of mastodon

: a type of animal that was related to the mammoth and that lived in ancient times

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Spanish Central: Translation of mastodon

Nglish: Translation of mastodon for Spanish Speakers Encyclopedia article about mastodon

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