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adjective B2 Upper-Intermediate Common

underground

uhn-duh-GROWND

Underground (adjective) means Located beneath the surface of the ground. Example: “The city has an extensive underground parking system.”

adjective
1
Located beneath the surface of the ground.
"The city has an extensive underground parking system."
2
Hidden from public view or authority; secretive.
"The rebels ran an underground network to smuggle supplies."
3
Relating to art, music, or culture outside the mainstream.
"She got her start in the underground music scene."
noun
1
A subway or train system running below street level, especially in London.
"We took the Underground to get to the museum."

How to use underground

Learner’s notes

In plain EnglishBelow the surface, or by extension, hidden from mainstream view — whether that's a resistance movement or an art scene.

UK vs US

In the UK, "the Underground" (or "the Tube") refers to London's subway; Americans would say "subway."

Common pairings
underground railway underground music go underground

Word forms

more underground comparative, more underground comparative, undergrounded past tense, undergrounds plural, undergrounds singular, most underground superlative, most underground superlative

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Test yourself on “underground” A quick quiz — meaning, synonyms & usage

Fill the gap

Can you complete this real example?

The city has an extensive _____ parking system.

Etymology

From Middle English undergrounde, from under + ground.

Origin: Middle English

Related words

Rhymes for underground

See all rhymes for underground →

Frequently asked questions

What does “underground” mean?

The word “underground” means located beneath the surface of the ground. In plain terms, below the surface, or by extension, hidden from mainstream view — whether that's a resistance movement or an art scene.

How do you pronounce “underground”?

“Underground” is pronounced uhn-duh-GROWND (/ˌʌn.dəɹˈɡɹaʊnd/ in IPA).

How do you use “underground” in a sentence?

Here is “underground” used in a sentence: “The city has an extensive underground parking system.”

What part of speech is “underground”?

Depending on how it is used, “underground” can be an adjective and a noun.

Where does the word “underground” come from?

The word “underground” comes from Middle English. From Middle English undergrounde, from under + ground.

Is “underground” a common word?

“Underground” is a fairly common word in modern English, usually learned at around the B2 level.

How many meanings does “underground” have?

“Underground” has 4 distinct senses listed in this dictionary. The most common is: located beneath the surface of the ground.

What is the difference between underground and subterranean?

Both words describe something located beneath the surface of the ground, but subterranean is more formal and technical, often used in scientific or geological contexts. Underground is the everyday term and can also carry the extra meaning of something hidden or secretive, which subterranean does not.

When does underground mean secret rather than beneath the ground?

Underground means secret or hidden from public view or authority when it describes activity, movements, or people operating outside official channels, as in an underground resistance or underground press. The literal meaning of beneath the surface applies to physical locations such as an underground tunnel or car park.

Can underground be used as a noun or an adverb?

Yes. Besides being an adjective, underground works as a noun for a secret organization or, in British English, for a subway system such as the London Underground. As an adverb it describes movement or position below the surface, as in the pipes run underground.

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