subterranean

adjective

sub·​ter·​ra·​nean ˌsəb-tə-ˈrā-nē-ən 

-nyən

variants or less commonly subterraneous

ˌsəb-tə-ˈrā-nē-əs 

-nyəs

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.

Synonyms

• belowground
• subsurface
• underground

Examples of subterranean in a Sentence

a subterranean bunker that supposedly could withstand even an atomic blast

Recent Examples on the Web

And this is an apt name for this chapter as all the traumatized denizens of the bunkers suffer restrictions from barricades, both physical and emotional, as their unnatural subterranean life seems to be cartwheeling out of control since Juliette took a stroll outside. —Jeff Spry, Space.com, 23 Dec. 2024

Inside Llewyn Davis, The Marvelous Mrs. Maisel, and A Complete Unknown immerse us in intimate, sometimes subterranean performance spaces. —David Browne, Rolling Stone, 22 Dec. 2024

Hudbay’s proposed Copper World mine is among the most visible and divisive of the state’s emerging prospects if only because its pits would take down a ridge and change the natural skyline visible from downtown Tucson, while also raising fears about the city’s subterranean water supply. —Brandon Loomis, The Arizona Republic, 19 Dec. 2024

Scientists estimate between 50 and 80 percent of Earth's microbial cells may live in these subterranean ecosystems. —Benedict Cosgrove, Newsweek, 19 Dec. 2024

Word History

Etymology

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

First Known Use

1603, in the meaning defined at sense 1

Kids Definition

subterranean

adjective

sub·​ter·​ra·​nean ˌsəb-tə-ˈrā-nē-ən 

-nyən

1

: being, lying, or operating under the surface of the earth

2

: existing or working in secret : hidden