fos·sil | \ ˈfä-səl \

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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Synonyms & Antonyms for fossil

Synonyms: Noun

antediluvian, fogy (also fogey), fuddy-duddy, reactionary, stick-in-the-mud, stuffed shirt

Antonyms: Noun

hipster, modern, trendy

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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


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

Building a brain To investigate, Muotri and his colleagues compared the genome of Neanderthals (previously extracted from fossil bones and sequenced by other researchers) with that of modern humans. Laura Geggel /, NBC News, "Why tiny Neanderthal brains are now growing in petri dishes," 27 June 2018 LiveScience reports that in 2002, for instance, a little fossil trail discovered in Canada was 520 million years old. Jason Daley, Smithsonian, "Oldest Footprints Show When Life On Earth Got Legs," 11 June 2018 Although the tracks are technically not fossil, they are treated as such under Utah code and can result in a felony charge for anyone who destroys the prehistoric relics. Fox News, "Tourists unknowingly toss dinosaur tracks into lake at a Utah state park," 8 May 2018 The OpenWings Project team will be working with a paleontologist to integrate fossil evidence, Chesser says. Kat Eschner, Smithsonian, "What We Can Learn From a New Bird Tree of Life," 21 Apr. 2018 Massimo Bernardi of the Museum of Sciences in Trento, Italy, and his colleagues looked in particular at fossil animal tracks (see picture above) in the Dolomite mountains, a part of the Alps to the north-east of Trento. The Economist, "Fossil tracks in the Alps help explain dinosaur evolution," 19 Apr. 2018 That model is based on a combination of fossil evidence from sites like Qafzeh and Skhul Cave in Israel and mitochondrial DNA studies that link most non-African populations to the group that left that continent 65,000 years ago. Kiona N. Smith, Ars Technica, "Saudi Arabian fossil find puts finger on the story of human dispersal," 9 Apr. 2018 The higher priority is maximizing the inherent flexibility of the fossil thermal fleet. David Roberts, Vox, "Solar power’s greatest challenge was discovered 10 years ago. It looks like a duck.," 31 Mar. 2018 There is also fossil evidence of marine extinctions that could be explained by significant ocean acidification, the researchers say. Scott K. Johnson, Ars Technica, "End-Cretaceous asteroid impact seems to have juiced seafloor volcanoes," 8 Feb. 2018

Recent Examples on the Web: Noun

The best place to find coral fossils are along the shores of Lake Huron, Knightstep said. Caroline Blackmon, Detroit Free Press, "Where to find 5 of Michigan's coolest rocks," 28 June 2018 In Tennessee, an 11-year old girl recently found a 475-million-year-old fossil. David Grossman, Popular Mechanics, "12 Year Old Girl Develops Pollution-Detecting Robot To Help Save the Ocean," 26 June 2018 In an interview last summer, Radha Muthiah, then the Alliance’s chief executive, said the Alliance was never against propane stoves, but should have been more direct about its openness to a fossil-fuel solution. Sara Morrison, USA TODAY, "In developing world, an expensive push to reduce cooking fire deaths falls short," 13 July 2018 But those calculations omit a key variable: someone still needs to pay for the existing fossil-fuel infrastructure. Justin Worland/pueblo, Time, "How One Industrial City Is Fighting to Go Green," 12 July 2018 His career was built around quietly and incrementally advancing the interests of the fossil-fuel industry, chiefly by weakening or delaying federal regulations. New York Times, "How Andrew Wheeler, the New Acting E.P.A. Chief, Differs From Scott Pruitt," 5 July 2018 Such a world could also feature the myriad new shapes, sizes, colors, and textures that fossil finds are revealing at an astonishing rate. Katherine J. Wu, Smithsonian, "Five Ways Real Science Would Make the New Jurassic World So Much Better," 12 June 2018 The embarrassment brings no particular substantive benefit, since if Pruitt stepped down, he would be replaced by a deputy who is equally willing and able to let fossil-fuel companies run the agency. Jonathan Chait, Daily Intelligencer, "Why Hasn’t Trump Fired Scott Pruitt? Because Pruitt Can Fire Robert Mueller.," 3 July 2018 The measure would put an escalating fee on most fossil-fuel emissions, adding an estimated 14 cents to the cost of a gallon of gasoline at the pump. Hal Bernton, The Seattle Times, "Fight heats up over Washington state carbon ‘fee’ likely to make fall ballot," 2 July 2018

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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The first known use of fossil was in 1665

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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

: a person whose ideas are very old-fashioned or out-of-date


fos·sil | \ ˈfä-səl \

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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Comments on fossil

What made you want to look up fossil? Please tell us where you read or heard it (including the quote, if possible).


to make amends

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