subterranean

American  

[suhb-tuh-rey-nee-uhn] / ˌsʌb təˈreɪ ni ən /

adjective

1. existing, situated, or operating below the surface of the earth; underground.

2. existing or operating out of sight or secretly; hidden or secret.

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noun

1. a person or thing that is subterranean.

2. a subterrane.

subterranean British  

/ ˌsʌbtəˈreɪnɪən /

adjective

1. Also: subterraneous.   subterrestrial.  situated, living, or operating below the surface of the earth

2. existing or operating in concealment

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Other Word Forms

• subterraneanly adverb
• subterraneously adverb

Etymology

Origin of subterranean

1595–1605; < Latin subterrāne ( us ) ( subterrane ) + -an

Example Sentences

The proposals included a two-storey "subterranean suite" beneath the No 10 garden, featuring a 200-seat conference room that could double as a "safe haven" in the event of a terror attack.

From BBC

The plotting doesn’t have any subterranean levels either, trusting solely in its primal display of sweat, hormones and heartbreak.

From Los Angeles Times

"At the very least, I expect England to have their second-best Ashes since 1990, which is, admittedly, an almost subterraneanly low bar. And I may reassess after 0.5 seconds of the series. Again."

From BBC

Sometimes I find myself underground, following the path of a worm as it burrows through miles of subterranean soil.

From Literature

Buying and installing subterranean bins is also expensive, compared to wheelie bins, so cash-strapped councils might not be able to afford them in large numbers.

From BBC