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

Did you know?

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 of subterranean

• underground

Examples of subterranean in a Sentence

a subterranean bunker that supposedly could withstand even an atomic blast

Recent Examples on the Web

On a purely logistical level, the practice of storing wine in a subterranean chamber is useful for maintaining cool, consistent temperatures that are conducive to aging wine. — Nicole Kliest, Vogue, 23 June 2026

Alongside the communal dining, lounge and bar areas, is a clever subterranean wine cellar, an outdoor BBQ and dining area overlooking the riverbed, and a deck in the perfect spot for viewing the waterhole. — Sarah Kingdom, Forbes.com, 21 June 2026

Be sure to hit the subterranean SoWa Vintage Market for thrifting finds, and on weekends from spring through fall the outdoor SoWa Open Market sets up shop with local vendors, artisans, food purveyors, farmers, and food and drink trucks selling their wares in a fun, alfresco setting. — Shannon McMahon, Condé Nast Traveler, 17 June 2026

Then comes the subterranean twist. — Mrigakshi Dixit, Interesting Engineering, 17 June 2026

Word History

Etymology

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

First Known Use

1603, in the meaning defined at sense 1

Rhymes for subterranean

• romanian
• roumanian
• rumanian
• ukrainian
• cenomanian
• lithuanian
• pennsylvanian
• pomeranian
• mediterranean

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