fossil

American  

[fos-uhl] / ˈfɒs əl /

noun

1. any remains, impression, or trace of a living thing of a former geologic age, as a skeleton, footprint, etc.

2. a markedly outdated or old-fashioned person or thing.

3. a linguistic form that is archaic except in certain restricted contexts, as nonce in for the nonce, or that follows a rule or pattern that is no longer productive, as the sentence So be it.

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adjective

1. of the nature of a fossil.

   fossil insects.

2. belonging to a past epoch or discarded system; antiquated.

   a fossil approach to economics.

fossil British  

/ ˈfɒsəl /

noun

1. 1. a relic, remnant, or representation of an organism that existed in a past geological age, or of the activity of such an organism, occurring in the form of mineralized bones, shells, etc, as casts, impressions, and moulds, and as frozen perfectly preserved organisms

   2. ( as modifier )

      fossil insects

2. informal

   1. a person, idea, thing, etc, that is outdated or incapable of change

   2. ( as modifier )

      fossil politicians

3. linguistics a form once current but now appearing only in one or two special contexts, as for example stead , which is found now only in instead ( of ) and in phrases like in his stead

4. obsolete any rock or mineral dug out of the earth

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fossil Scientific  

/ fŏs′əl /

1. The remains or imprint of an organism from a previous geologic time. A fossil can consist of the preserved tissues of an organism, as when encased in amber, ice, or pitch, or more commonly of the hardened relic of such tissues, as when organic matter is replaced by dissolved minerals. Hardened fossils are often found in layers of sedimentary rock and along the beds of rivers that flow through them.

2. See also index fossil microfossil trace fossil

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fossil Cultural  

1. The evidence in rock of the presence of a plant or an animal from an earlier geological period. Fossils are formed when minerals in groundwater replace materials in bones and tissue, creating a replica in stone of the original organism or of their tracks. The study of fossils is the domain of paleontology. The oldest fossils (of bacteria) are 3.8 billion years old.

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Discover More

The term is used figuratively to refer to a person with very old-fashioned or outmoded viewpoints: “That old fossil thinks that men should wear suits at the theater!”

Other Word Forms

• fossillike
  adjective
• subfossil
  noun

Etymology

Origin of fossil

First recorded in 1555–65; from Latin fossilis “dug up,” from foss(us) “dug” (past participle of fodere “to dig”) + -ilis -ile ( def. ); replacing earlier fossile, from French

Explanation

Fossils are the really, really old remains of a plant or animal — so old they've turned to stone. Fossil is also an insult for an old or old-fashioned person. Fossils are very important to scientists who study animals: they're one of the ways we learn about the beasts and critters of the past. A fossil is an imprint of the bones of that animal in rock or stone. If you see a reconstruction of a dinosaur in a museum, scientists used fossils to figure out how it should look. Also, calling someone a fossil is like calling them a geezer or old fogey. It's not a compliment.

Example Sentences

Later, during the administration’s summer-long festival to commemorate the signing of the Declaration of Independence, IndyCars will race in a fossil fuel-burning extravaganza around and around the National Mall — home to the U.S.

From Los Angeles Times • May 29, 2026

Evidence from ancient soils and fossil plants suggests the region looked very different from modern Patagonia.

From Science Daily • May 29, 2026

Tuvalu has entrusted management of its single-largest financial asset to advisory firm Mercer, which has invested in funds holding stakes in major fossil fuel companies, according to financial records and government reports reviewed by AFP.

From Barron's • May 28, 2026

“It’s a risk multiplier for the already elevated chances we now have for extreme events due to the burning of fossil fuels,” Watkins said.

From The Wall Street Journal • May 28, 2026

After the meal, Adam took a quick peek at Teddy’s fossil finds, and then we went upstairs to my room and closed the door.

From "If I Stay" by Gayle Forman

Related Words

• relic
• skeleton
• specimen
• trace