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.
Then there’s the two subterranean lakes that have made the cave so iconic. Megan Dubois, Southern Living, 23 Oct. 2025 The brutalist building has 11 rooms of varying sizes and views, but one standout suite is the subterranean bunker room with no windows. Susmita Baral, Travel + Leisure, 23 Oct. 2025 These will need to be fenced off while large international construction firms take on the challenges of rubble, explosives, bodies and collapsed subterranean tunnels before tall buildings can rise. Shelly Culbertson, MSNBC Newsweek, 22 Oct. 2025 Business leaders and boosters—if not the public library’s archivist—thought rumors and legends and sub-cellars, basements, coal chutes, and other subterranean utility spaces made for a marketable product. JSTOR Daily, 20 Oct. 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

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Cite this Entry

“Subterranean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/subterranean. Accessed 25 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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