ich·​thyo·​saur | \ ˈik-thē-ə-ˌsȯr \

Definition of ichthyosaur

: any of an order (Ichthyosauria) of extinct marine reptiles of the Mesozoic specialized for aquatic life by a streamlined body with a long snout, limbs reduced to small fins for steering, and a large lunate caudal fin

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Other Words from ichthyosaur

ichthyosaurian \ ˌik-​thē-​ə-​ˈsȯr-​ē-​ən \ adjective or noun

Examples of ichthyosaur in a Sentence

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According to a press release, the researchers dated the bones to 205 million years ago, and estimate that in life the Lilstock ichthyosaur would have been up to 85 feet long, edging well into blue whale territory. Jason Daley, Smithsonian, "This Ancient Reptile Was One of the Most Massive Creatures That Ever Lived," 10 Apr. 2018 In water, the laws of hydrodynamics explain the sleek, tapered body shape shared by the shark (a fish), the dolphin (a mammal) and the extinct ichthyosaur reptile, which plied the Mesozoic oceans. Charles S. Cockell, WSJ, "The Limits of Extra-Terrestrial Freakiness," 7 June 2018 Fossils of ichthyosaur—extinct carnivorous marine reptiles—are not uncommon. Julissa Treviño, Smithsonian, "Fossilized ‘Sea Monster’ Found Pregnant With Eight Babies," 10 Apr. 2018 The fossilized remains belonged to a ichthyosaur that lived between 200 and 190 million years ago, during the Jurassic Period. Julissa Treviño, Smithsonian, "Fossilized ‘Sea Monster’ Found Pregnant With Eight Babies," 10 Apr. 2018 Experts estimate the body of the ichthyosaur was approximately 85 feet in length. Chris Ciaccia, Fox News, "Massive 205-million-year-old ichthyosaur fossil discovered, 'one of the largest animals ever'," 11 Apr. 2018 In February 2016, a team from the University of Delhi, Kutch University, and the universities of Kiel and Erlangen-Nuremberg in Germany unveiled a 150-million-year-old, nearly complete skeleton of an ichthyosaur. Sanjay Kumar, Science | AAAS, "India’s paleontologists fight destruction of its fossil riches," 4 Apr. 2018 Though the prehistoric oceans were teeming with fierce marine predators like the ichthyosaurs and mesosaurs, those leviathans were not dinosaurs, but rather marine reptiles like sea turtles. Nicholas St. Fleur, New York Times, "This Duck-Like Dinosaur Could Swim. That Isn’t the Strangest Thing About it.," 6 Dec. 2017 For one, the fossil represents the first Jurassic-era ichthyosaur ever found India. Brigit Katz, Smithsonian, "Scientists Unearth Near-Complete Marine Reptile Fossil in India," 27 Oct. 2017

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

1830, in the meaning defined above

History and Etymology for ichthyosaur

ultimately from Greek ichthy- + sauros lizard

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The first known use of ichthyosaur was in 1830

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