subterranean

adjective

sub·​ter·​ra·​nean ˌsəb-tə-ˈrā-nē-ən How to pronounce subterranean (audio)
-nyən
variants or less commonly subterraneous
1
: being, lying, or operating under the surface of the earth
2
: existing or working in secret : hidden
a subterranean network of criminals
subterraneanly adverb
or less commonly subterraneously

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Go Underground With Subterranean

A tunnel is a subterranean road or pathway, and a subway is a subterranean railway. The subterranean vaults at Fort Knox hold billions of dollars of gold reserves. Subterranean reservoirs called aquifers are tapped for water; in places where the pressure on the subterranean water is great enough, a hole drilled in the ground will bring it bubbling to the surface.

Examples of subterranean in a Sentence

a subterranean bunker that supposedly could withstand even an atomic blast
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Unable to plausibly explain to the authorities what happened — or why she’s covered in her friends’ blood — Sarah is forced back to the subterranean depths to help locate her five missing companions. Caitlin White, Variety, 3 Oct. 2025 While a few worlds in the Milky Way are believed to have liquid water hiding beneath a frozen surface, Enceladus isn't quite as secretive about its subterranean ocean. Eric Lagatta, USA Today, 3 Oct. 2025 The aim is to reduce evacuation zones and improve forecasting of risks to people, buildings, and subterranean infrastructure. Kaif Shaikh, Interesting Engineering, 1 Oct. 2025 Even though the house is long gone, I was allowed to walk through its subterranean lower levels and could vividly imagine families hiding in the storage areas. Literary Hub, 30 Sep. 2025 See All Example Sentences for subterranean

Word History

Etymology

Latin subterraneus, from sub- + terra earth — more at thirst

First Known Use

1603, in the meaning defined at sense 1

Time Traveler
The first known use of subterranean was in 1603

Browse Nearby Words

Cite this Entry

“Subterranean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/subterranean. Accessed 16 Oct. 2025.

Kids Definition

subterranean

adjective
sub·​ter·​ra·​nean ˌsəb-tə-ˈrā-nē-ən How to pronounce subterranean (audio)
-nyən
1
: being, lying, or operating under the surface of the earth
2
: existing or working in secret : hidden

More from Merriam-Webster on subterranean

Last Updated: - Updated example sentences
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