1
as in clandestine
undertaken or done so as to escape being observed or known by others
an underground operation to smuggle ancient artifacts out of the country
Synonyms & Similar Words
Relevance
Antonyms & Near Antonyms
2
as in subterranean
being, situated, or operating beneath the surface of the earth
an underground shopping mall that is part of the city's subway system
Synonyms & Similar Words
Antonyms & Near Antonyms
as in resistance
a secret organization in a conquered country fighting against enemy forces
joined the underground while still a teenager
Synonyms & Similar Words
as in undercover
Related Words
Dissimilar Words
Example Sentences
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Recent Examples of underground
Lauren Schuster, Kansas City Star, 22 May 2026
Berlin has turned its underground club energy into alcohol-free nightlife.
—Lauren Schuster, Charlotte Observer, 22 May 2026
Sujita Sinha, Interesting Engineering, 27 Apr. 2026
Household water largely comes from underground, the same aquifer that connects to the springs.
—Letters To The Editor, The Orlando Sentinel, 24 Apr. 2026
ArsTechnica, 13 May 2026
The digital collection disseminated underground in Cuba served as a substitute for broadband Internet.
—Bill Kopp, SPIN, 13 May 2026
See All Example Sentences for underground
Adjective
Berlin is channeling its underground club energy into sober dance parties.
—Lauren Schuster, Kansas City Star, 22 May 2026
Berlin has turned its underground club energy into alcohol-free nightlife.
—Lauren Schuster, Charlotte Observer, 22 May 2026
Noun
This plant is intended to store large quantities of hydrogen underground.
—Sujita Sinha, Interesting Engineering, 27 Apr. 2026
Household water largely comes from underground, the same aquifer that connects to the springs.
—Letters To The Editor, The Orlando Sentinel, 24 Apr. 2026
Adverb
Murdock and his vigilante allies have been forced underground, while Fisk imposes multiple harsh authoritarian measures on the city to cement his power.
—ArsTechnica, 13 May 2026
The digital collection disseminated underground in Cuba served as a substitute for broadband Internet.
—Bill Kopp, SPIN, 13 May 2026
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
-
But in the current political climate, clandestine behaviors could win out.—
Robin George Andrews,
Scientific American,
19 May 2026
-
These relations are not based on secrecy or clandestine arrangements.—
Emma Bussey,
FOXNews.com,
17 May 2026
Adjective
-
The house spans almost 5,400 square feet, plus an additional 2,200 square feet of finished subterranean space executed to the same standard as the rest of the house.—
Mark David,
Robb Report,
22 May 2026
-
These subterranean passageways are significant in Hawaiian culture, providing shelter for the ancient communities and and being places for ceremonies and burials.—
Kathleen Wong,
USA Today,
20 May 2026
Noun
-
Bode and Jake — whose patience with Danny's resistance to being helped is wearing mighty thin — manage to free Danny and relocate to the roof.—
Britt Hayes,
Entertainment Weekly,
23 May 2026
-
Shoppers are impressed with the wrinkle resistance of this pick and dig its flattering fit and soft fabric.—
Annie Blackman,
InStyle,
23 May 2026
Adjective
-
Gaff reportedly obliged, providing the undercover detectives with a sample that was subsequently sent through the federal database CODIS, where investigators ultimately linked him to Weaver's murder.—
Julia Bonavita,
FOXNews.com,
18 May 2026
-
Essayli on Monday confirmed that Armstrong became known to the DOJ after an undercover video was posted online by James O'Keefe, the founder of conservative nonprofit Project Veritas.—
Austin Turner,
CBS News,
18 May 2026
Adverb
-
Various additional actions like this are stealthily undertaken by the vendor.—
Lance Eliot,
Forbes.com,
17 May 2026
-
Fukada stealthily shades in these subtleties of feeling into the story with exacting skill, creating a drama that touches on social issues but never feels issues-driven.—
Leslie Felperin,
HollywoodReporter,
13 May 2026
Adjective
-
More details about the Cavs/The Realest partnership To ensure authenticity, The Realest oversees every collectible item to have patent-pending covert markings and tamper resistant holograms.—
Mark Medina,
Forbes.com,
23 May 2026
-
The sizable bridal party took some work and covert planning.—
Rosemary Feitelberg,
Footwear News,
20 May 2026
Adverb
-
Haslach also admitted to surreptitiously taking a photo of a minor in a swimsuit by positioning his cellphone under a classroom desk.—
Nick Ferraro,
Twin Cities,
1 May 2026
-
Sometimes the batteries on the trackers would run low, and McGovern’s team would need to remove and recharge the devices, before surreptitiously replacing them.—
Ed Caesar,
New Yorker,
30 Apr. 2026
Adjective
-
Get Ready: Katy Perry Has Released a Sneak Peek of Her New Song And the internet has receipts.—
Mehera Bonner,
Marie Claire,
15 Mar. 2017
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 25 May. 2026.
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