subterranean

adjective sub·ter·ra·nean \ ˌsəb-tə-ˈrā-nē-ən , -nyən \

variants: or less commonly subterraneous play \ˌsəb-tə-ˈrā-nē-əs, -nyəs\

Updated on: 20 May 2018

Definition of subterranean

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

2 : existing or working in secret : hidden

a subterranean network of criminals

—

subterraneanly

or less commonly subterraneously adverb

See subterranean defined for English-language learners

See subterranean defined for kids

Examples of subterranean in a Sentence

a subterranean bunker that supposedly could withstand even an atomic blast

Recent Examples of subterranean from the Web

Burney Creek flows over the brink and is mixed with subterranean flow from lava tubes at mid-wall to create a curtain effect.

— tom stienstra, San Francisco Chronicle, "Northern California’s 12 splashiest waterfalls," 17 May 2018
More than 500,000 subterranean termites were introduced into the soil around the house in early March.

— james rogers, Fox News, "Watch 500,000 termites devastate a tiny house," 16 May 2018
Those competitors will create subterranean environments with software from Open Robotics, which also makes the Robot Operating System that powers a whole slew of machines around the world.

— matt simon, WIRED, "Darpa's Next Challenge? A Grueling Underground Journey," 15 May 2018
The observations support the idea that Europa has a vast subterranean ocean buried beneath about 10 km of icy crust—an ocean with more water than all the oceans of Earth combined.

— john wenz, Popular Mechanics, "NASA Spacecraft Likely Flew Though a Europa Water Plume in 1997," 14 May 2018
Israel is building a subterranean barrier to detect and prevent attack tunnels.

— BostonGlobe.com, "Israel bombs Gaza tunnel, closes key crossing after attack," 12 May 2018
Israel is building a subterranean barrier to detect and prevent attack tunnels.

— fares akram, The Seattle Times, "Israel bombs Gaza tunnel, closes key crossing after attack," 12 May 2018
Israel is building a subterranean barrier to detect and prevent attack tunnels.

— chicagotribune.com, "Israel bombs Gaza tunnel, closes key crossing amid weekly mass protests," 12 May 2018
Israel is building a subterranean barrier to detect and prevent attack tunnels.

— Washington Post, "Israel bombs Gaza tunnel, closes key crossing after attack," 12 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'subterranean.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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.