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
Christian Zilko, IndieWire, 5 Sep. 2025
Moving the utilities underground also reduces the need for future power shutoffs.
—Michael Slaten, Oc Register, 29 Aug. 2025
Jason Ma, Fortune, 7 Sep. 2025
In its world, resurrected mammoths roam, AI governs underground facilities, and human-animal hybrids embody both triumph and ambiguity.
—Charlie Fink, Forbes.com, 6 Sep. 2025
Thomas Gounley, Denver Post, 14 Aug. 2025
The speaker system—designed in part by Shepherd and Tom Smith, co-founder of the famed underground Cosmic Slop party in Leeds—was meant to reference the disco setups at New York’s Paradise Garage and sub-heavy sound systems of Jamaica.
—Jeremy D. Larson, Pitchfork, 14 Aug. 2025
See All Example Sentences for underground
Adjective
Aaron Taylor-Johnson stars as Will Tranter, a major in the British Army specializing in explosives, who is called in after an old World War II bomb is discovered underground at a London construction site.
—Christian Zilko, IndieWire, 5 Sep. 2025
Moving the utilities underground also reduces the need for future power shutoffs.
—Michael Slaten, Oc Register, 29 Aug. 2025
Noun
The world’s largest underground, iron-ore mine has forced the village’s herders to lead their reindeer through a longer and harder migration route.
—Jason Ma, Fortune, 7 Sep. 2025
In its world, resurrected mammoths roam, AI governs underground facilities, and human-animal hybrids embody both triumph and ambiguity.
—Charlie Fink, Forbes.com, 6 Sep. 2025
Adverb
Some would be tucked behind the ground-floor commercial space, with the rest underground.
—Thomas Gounley, Denver Post, 14 Aug. 2025
The speaker system—designed in part by Shepherd and Tom Smith, co-founder of the famed underground Cosmic Slop party in Leeds—was meant to reference the disco setups at New York’s Paradise Garage and sub-heavy sound systems of Jamaica.
—Jeremy D. Larson, Pitchfork, 14 Aug. 2025
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
-
The Bundy family’s statement noted this and said their destination was not clandestine, as the FBI document alleged.—
Nicole Blanchard,
Idaho Statesman,
7 Sep. 2025
-
The result was the Commandos, who operated in clandestine raids behind the lines to harass the enemy with remarkable success.—
New Atlas,
New Atlas,
7 Sep. 2025
Adjective
-
Afterward, retreat to the spa’s relaxation lounge—where a glowing copper teardrop floats above cedar banquettes—while next door, the subterranean fitness center boasts Technogym gear and treadmills—all below the waterline.—
Lewis Nunn,
Forbes.com,
6 Sep. 2025
-
But while the area has been evacuated, a gang of robbers led by James is drilling into the subterranean vault of a nearby bank.—
Carole Horst,
Variety,
5 Sep. 2025
Noun
-
Of course there's always resistance in neighborhoods.—
Kristen Edgreen Kaufman,
Forbes.com,
8 Sep. 2025
-
Stand with a resistance band in front of you and grab the ends.—
Jakob Roze,
Health,
8 Sep. 2025
Adjective
-
Cameron Crowe researched what would become his debut script by going undercover as a high school student for a full year in what can only be described as a 21 Jump Street stunt.—
Paul Fitzgerald,
Rolling Stone,
8 Sep. 2025
-
Further, this legislation is unnecessary if it is truly intended to apply to undercover officers.—
Charles Champion,
Oc Register,
8 Sep. 2025
Adverb
-
Karalis supplies his colleagues with fluorescent orange utility uniforms and stealthily leads them through the back door of the Bank Al Muraqabah, located just below Rahim’s building.—
Peter Debruge,
Variety,
6 Sep. 2025
-
Others are stealthily looking for deals, sales, using layaway options and trading brand preferences for affordability.—
Leah Olajide,
Freep.com,
26 Aug. 2025
Adjective
-
Moreover, the lobster boat and the Mako were covert FBI assets carefully disguised as legitimate smuggling vessels.—
Martin Suarez,
Rolling Stone,
13 Sep. 2025
-
If compromised, malicious radios inside them could be used for simultaneous outages or covert data collection, the FHWA warned.—
Sujita Sinha,
Interesting Engineering,
11 Sep. 2025
Adverb
-
By the episode's end, however, he's set his sights on Morgan, having surreptitiously slipped a note into her grocery bag.—
Randall Colburn,
Entertainment Weekly,
6 Sep. 2025
-
Inevitably, a few students were surreptitiously checking smuggled screens that day.—
Christopher Bonanos,
Curbed,
5 Sep. 2025
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 14 Sep. 2025.
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