tri·​lo·​bite | \ˈtrī-lə-ˌbīt \

Definition of trilobite 

: any of numerous extinct Paleozoic marine arthropods (group Trilobita) having the segments of the body divided by furrows on the dorsal surface into three lobes

Illustration of trilobite

Illustration of trilobite

trilobite fossil

Examples of trilobite in a Sentence

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The family reached out to a paleontologist at the nearby University of Tennessee, who was able to confirm that Taylor had found a complete trilobite. David Grossman, Popular Mechanics, "11-Year-Old Stumbles Across 475-Million-Year-Old Fossil," 4 May 2018 One of the most successful early animals, trilobites lived in variety of lifestyles. David Grossman, Popular Mechanics, "11-Year-Old Stumbles Across 475-Million-Year-Old Fossil," 4 May 2018 Think trilobites to the woolly mammoth with T. rex in between. Susan Faust, San Francisco Chronicle, "Roundup of new children’s books," 24 May 2018 His kite was in the shape of a trilobite, an ancient marine animal that lived some 500 million years ago. Frank Vaisvilas, Daily Southtown, "Giant sea creatures, other colorful kites take to skies over Will County during festival," 1 May 2018 And while that sucked for trilobites, life was eventually able to make a comeback. David Grossman, Popular Mechanics, "How a Gamma Ray Burst Could Cause Mass Extinction From Billions of Miles Away," 22 Dec. 2017 As the researchers note in the study, another trilobite species, Holmia kjerulfi, evolved just a few million years later and had even better eyesight, approximating the modern dragonfly. Jason Daley, Smithsonian, "Gaze Into a 530-Million-Year-Old Eye, the Oldest Yet Discovered," 11 Dec. 2017 Plus, everybody's favorite Cambrian animal, the trilobite, diversified like crazy and moved into many new habitats during this time. Annalee Newitz, Ars Technica, "If you liked the Cambrian Explosion, you’ll love the Ordovician Radiation," 21 Nov. 2017 There are more than 20,000 species of trilobite previously identified, Donahue reports. Lauren Young, Smithsonian, "These Spectacularly Preserved Trilobite Fossils Come Complete With Guts, Gills and Legs," 8 Feb. 2017

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

1832, in the meaning defined above

History and Etymology for trilobite

ultimately from Greek trilobos three-lobed, from tri- + lobos lobe

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The first known use of trilobite was in 1832

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a soft lustrous wool fabric with mohair

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