tar pit

American  

[tahr pit] / ˈtɑr ˌpɪt /

noun

plural

tar pits

1. an accumulation of natural tar or asphalt that has seeped upward to the earth's surface, especially one that has acted as a natural trap into which animals have fallen, sunk, and had their bones preserved.

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tar pit Scientific  

1. An accumulation of natural tar or asphalt at the Earth's surface, especially one that traps animals and preserves their hard parts. Tar pits form when petroleum in subterranean petroleum-bearing rocks oozes up to the surface. As it rises, the petroleum loses its volatile components, forming a thick tar or asphalt deposit.

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Example Sentences

Economic growth is the only way out of the tar pit.

From The Wall Street Journal • Nov. 27, 2025

But the asphalt of a tar pit is rich in very old carbon, which is largely devoid of carbon-14.

From Science Magazine • Aug. 16, 2023

But thanks to the federal and local governments, an administrative tar pit made it extremely difficult for the private investors to build their energy plants.

From Slate • Jan. 27, 2021

It came during a mission in which I was tasked with recovering a machine that a paleontologist had been using to collect samples from a tar pit.

From New York Times • Mar. 3, 2020

Just ask a long-grieving widow whose husband drowned in a medicinal tar pit, or a plucky young governess who spent more than half her life wondering whether she might someday see her parents again.

From "The Unseen Guest" by Maryrose Wood