mas·​to·​don | \ˈmas-tə-ˌdän, -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 \ ˌmas-​tə-​ˈdä-​nik \ adjective
mastodont \ ˈmas-​tə-​ˌdänt \ 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

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 The final stop on her mini-tour deals with fossils like the mastodon, which dates to the most recent Ice Age that ended around 10,000 years ago in Wisconsin. Brian E. Clark, Milwaukee Journal Sentinel, "A mastodon and a meteor older than Earth are highlights of the UW Geology Museum," 9 Mar. 2018 Aldermen approved a contract with Taylor Studios, in Rantoul, for $89,289 for the mastodon. Steve Lord, Aurora Beacon-News, "Mastodon model approved for Aurora exhibit at Phillips Park," 3 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

New Latin mastodont-, mastodon, from Greek mastos + odont-, odōn, odous tooth — more at tooth

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Statistics for mastodon

Last Updated

16 Nov 2018

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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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