fos·​sil | \ ˈfä-səl How to pronounce fossil (audio) \

Definition of fossil

 (Entry 1 of 2)

1 : preserved from a past geologic age fossil plants fossil water in an underground reservoir
2 : being or resembling a fossil
3 : of or relating to fossil fuel fossil energy sources



Definition of fossil (Entry 2 of 2)

1 : a remnant, impression, or trace of an organism of past geologic ages that has been preserved in the earth's crust — compare living fossil
2a : a person whose views are outmoded : fogy
b : something (such as a theory) that has become rigidly fixed
3 : an old word or word element preserved only by idiom (such as fro in to and fro)

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Did You Know?

A remnant, impression, or trace of an animal or plant of a past geologic age that has been preserved in the earth’s crust is called a fossil. Data from fossils are the primary source of information about the history of life on the earth. Only a small fraction of ancient organisms are preserved as fossils, and usually only organisms that have a solid skeleton or shell. Unaltered hard parts, such as the shells of clams, are relatively common in sedimentary rocks. The embedding of insects in amber and the preservation of mammoths in ice are rare but striking examples of the fossil preservation of soft tissues. Traces of organisms such as tracks and trails may also be preserved.

Examples of fossil in a Sentence

Noun some old fossil who thinks that a boy and a girl shouldn't be together unsupervised until they are engaged
Recent Examples on the Web: Adjective Because the remains of many recent and fossil urchins seem to have healed sizable fractures, the researchers say their subject likely lived long enough to begin to regenerate. Ian Randall, Science | AAAS, "Watch a half-dead sea urchin get menaced by a hungry crab—and live to tell the tale," 21 Apr. 2020 The new research looks only at the fossil side of the methane budget. Chris Mooney, Anchorage Daily News, "Methane is a hard-hitting greenhouse gas. Scientists say we’ve dramatically underestimated how much we’re emitting.," 19 Feb. 2020 Amber dealers suspected the fossil foot, originally found in the Hukawng Valley of Myanmar in 2014, belonged to a lizard, which are known for their long toes. Sabine Galvis, Science | AAAS, "This ancient bird sported a ginormous toe," 11 July 2019 And yet, nonetheless, the Earth's atmosphere today is full of ancient, fossil methane. Chris Mooney, Anchorage Daily News, "Methane is a hard-hitting greenhouse gas. Scientists say we’ve dramatically underestimated how much we’re emitting.," 19 Feb. 2020 Their findings showed that naturally occurring fossil methane levels are actually about 10 times lower than what past research had shown. Drew Kann, CNN, "Oil and gas production is contributing even more to global warming than was thought, study finds," 19 Feb. 2020 According to fossil evidence, shrimp existed some 350 million years ago. Gene Weingarten, Washington Post, "Gene Weingarten: Did you Google ‘I have no idea how to cook shrimp because I am a moron’? You’re in the right place.," 6 Feb. 2020 Plenty of evidence, including isotopic ratios in fossil bones, supports the idea that Neanderthals living along the Mediterranean coast ate shellfish, marine mammals, and fish. Kiona N. Smith, Ars Technica, "Neanderthals may have been shallow free divers, suggests a new study," 19 Jan. 2020 In fossil bones, most of the material that existed while the animal was alive gets slowly replaced over time by minerals. Steve Mirsky, Scientific American, "2 New Books Look at Evolution via Teeth and Tunnels," 1 July 2017 Recent Examples on the Web: Noun Adalatherium’s teeth are the strangest part of the fossil. Theresa Machemer, Smithsonian Magazine, "66-Million-Year-Old ‘Crazy Beast’ Finds a Taxonomical Home," 1 May 2020 And this tumultuous time also offers us a glimpse of what a fossil-free world would look like, Burkett argued, with cleaner air and rebounding ecosystems. Melody Schreiber, The New Republic, "The Coronavirus and the Limits of Individual Climate Action," 27 Apr. 2020 Found in southern Germany, the 150 million-year-old Archaeopteryx fossil combined reptilian and avian features. Jonathon Keats, Discover Magazine, "The Origins of Flight, From Birds to Bugs to Planes," 21 June 2019 The fossil is remarkably complete, an extremely rare find for ancient mammals that lived alongside the dinosaurs. Fox News, "66M-year-old 'crazy beast' discovered in Madagascar: An 'animal for which we don't have any real parallels'," 1 May 2020 The tiny fossil is unassuming, as dinosaur remains go. Riley Black, Scientific American, "Possible Dinosaur DNA Has Been Found," 17 Apr. 2020 The fossils were in rocks dating back to the Cretaceous period in the San Juan Basin in New Mexico. Ashley Strickland, CNN, "Newly discovered feathered dinosaur was one of the last raptors before extinction," 26 Mar. 2020 Voris, the lead author of the study, said scientists concluded the fossils were a new species by analyzing the fragments De Groot found. Li Cohen, CBS News, "The T. Rex may be the King of Lizards, but its new cousin is the "Reaper of Death"," 10 Feb. 2020 Other than the tyrannosaurs, the other fossils are mostly aquatic creatures. Eric Betz, Discover Magazine, "Tyrannosaurus Rex: Scary. Smart. Social?," 12 Apr. 2019

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


1665, in the meaning defined at sense 1


1736, in the meaning defined at sense 1

History and Etymology for fossil


earlier, "dug from the earth, preserved in the ground," borrowed from French & Latin; French fossile, borrowed from Latin fossilis "obtained by digging," from fodiō, fodere "to prod, jab, dig, remove by digging" (going back to Indo-European *bhedh-, *bhodh- "jab, dig," whence also Lithuanian bedù, bèsti "to stick, dig," Old Church Slavic bodǫ, bosti "to prick, stab," Hittite paddai "digs") + -tilis "produced by, characterized by (the action of the verb)"


derivative of fossil entry 1, or borrowed directly from Latin fossilis

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Time Traveler for fossil

Time Traveler

The first known use of fossil was in 1665

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Statistics for fossil

Last Updated

3 May 2020

Cite this Entry

“Fossil.” Dictionary, Merriam-Webster, Accessed 27 May. 2020.

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More Definitions for fossil



English Language Learners Definition of fossil

: something (such as a leaf, skeleton, or footprint) that is from a plant or animal which lived in ancient times and that you can see in some rocks
informal : a person whose ideas are very old-fashioned or out-of-date


fos·​sil | \ ˈfä-səl How to pronounce fossil (audio) \

Kids Definition of fossil

: a trace or print or the remains of a plant or animal of a past age preserved in earth or rock

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