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
Megan Hughes, Better Homes & Gardens, 6 July 2025
Especially in the case of those herbaceous perennials that overwinter underground as fleshy storage root systems, fall planting allows those roots to develop in the still warm soil without the stress of the heat of summer.
—Paul Cappiello, The Courier-Journal, 2 July 2025
Emma Burleigh, Fortune, 19 July 2025
Policy implications To extract oil and natural gas from underground reserves, heavy drilling equipment injects water and chemicals into the earth under high pressure.
—Lisa McKenzie, The Conversation, 17 July 2025
Joshua Siskin, Oc Register, 15 May 2025
But, of course, a facility like Fordow underground is dependent on a lot of infrastructure.
—ABC News, 15 June 2025
See All Example Sentences for underground
Adjective
Rhizomes are food storage root structures that grow underground horizontally.
—Megan Hughes, Better Homes & Gardens, 6 July 2025
Especially in the case of those herbaceous perennials that overwinter underground as fleshy storage root systems, fall planting allows those roots to develop in the still warm soil without the stress of the heat of summer.
—Paul Cappiello, The Courier-Journal, 2 July 2025
Noun
The marble does not explain the roughly $600 million in cost overruns for the project, now budgeted to cost $2.5 billion, which also includes the addition of an underground parking garage and new glass atria in the building’s courtyards.
—Emma Burleigh, Fortune, 19 July 2025
Policy implications To extract oil and natural gas from underground reserves, heavy drilling equipment injects water and chemicals into the earth under high pressure.
—Lisa McKenzie, The Conversation, 17 July 2025
Adverb
Its durability is attributable to clusters of stout underground rhizomes from which spears are produced.
—Joshua Siskin, Oc Register, 15 May 2025
But, of course, a facility like Fordow underground is dependent on a lot of infrastructure.
—ABC News, 15 June 2025
See All Example Sentences for underground
Recent Examples of Synonyms for underground
Adjective
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Speaking with Robbie Fox on the My Mom's Basement podcast, the former WWE Champion shared the story of the clandestine meeting.—
Andrew Ravens,
MSNBC Newsweek,
16 July 2025
-
Even when targeting America’s enemies, not all are supportive of clandestine cyberattacks.—
Thomas Brewster,
Forbes.com,
15 July 2025
Adjective
-
On the upper level, a trio of ocean-view guest suites with private baths are joined by a game room, while auto enthusiasts will get a thrill from the 16-car subterranean garage.—
Demetrius Simms,
Robb Report,
23 July 2025
-
Set in a historic 1894 stable, Stable Hall is live music venue that brings in renowned talent like Gillian Welch and David Rawlings, while Jazz, TX, by jazz pianist Doc Watkins hosts shows every night of the week an intimate, subterranean setting.—
Katie Chang,
Forbes.com,
23 July 2025
Noun
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Address resistance through education, value demonstration and gradual implementation that builds confidence over time.—
Sunil Kumar Puli,
Forbes.com,
31 July 2025
-
In this way, the era sits within the broader lineage of cultural expression that helped give rise to movements like Black Lives Matter, where self-definition and public presence became acts of resistance.—
Alexandra Jane,
Essence,
31 July 2025
Adjective
-
At the beginning of the season, host Alan Cumming picks the Traitors that will pit the Faithful against each other by murdering them one by one while trying to remain undercover.—
Armando Tinoco,
Deadline,
22 July 2025
-
Ogles cited an undercover video obtained by conservative news website Townhall which appears to show a university employee discussing the school’s Office of Hope, Unity, and Belonging.—
Ruben Montoya,
The Tennessean,
19 July 2025
Adjective
-
The bill would ban face coverings during public enforcement operations unless medically required or part of a covert investigation.—
Billal Rahman,
MSNBC Newsweek,
24 July 2025
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The human touch is also crucial for ensuring accountability with agentic AI use, particularly for security considerations like accountability and distinguishing a genuine user from a covert threat.—
Imran Aftab,
Forbes.com,
17 July 2025
Adjective
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Spelman will be cremated in a private ceremony Thursday, his family said.—
Emiliano Tahui Gómez,
Austin American Statesman,
25 July 2025
-
Appreciate Luxury with Great Views With more than 450 rooms, each with a private balcony overlooking Corpus Christi Bay, the Omni Hotel offers the city's most luxurious accommodations.—
Gabi De la Rosa,
Southern Living,
24 July 2025
Cite this Entry
“Underground.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/underground. Accessed 3 Aug. 2025.
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