1
as in clandestine
undertaken or done so as to escape being observed or known by others
an undercover operation to infiltrate the terrorist organization
Synonyms & Similar Words
Relevance
Antonyms & Near Antonyms
as in spy
a person who tries secretly to obtain information for one country in the territory of another usually unfriendly country
within the city was a well-organized fifth column, and these undercovers would make themselves known as soon as the invading forces breached the city limits
Synonyms & Similar Words
as in underground
Related Words
Dissimilar Words
Example Sentences
Examples are automatically compiled from online sources to
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Recent Examples of undercover
Elaine Mallon, The Washington Examiner, 24 June 2025
The items will be under 24-hour surveillance by more than 25 armed security guards, 360-degree cameras, undercover and uniformed police and canine units for the duration of Fanatics Fest.
—Larry Holder, New York Times, 21 June 2025
Guy Lawson, Rolling Stone, 24 Mar. 2024
Back at the hospital Jack tells Brady that working undercover took a lot of courage.
—Jessica Radloff, Glamour, 8 Sep. 2023
See All Example Sentences for undercover
Noun
On Monday, Akhtar met in person with an undercover agent posing as an Islamic State group operative.
—Elaine Mallon, The Washington Examiner, 24 June 2025
The items will be under 24-hour surveillance by more than 25 armed security guards, 360-degree cameras, undercover and uniformed police and canine units for the duration of Fanatics Fest.
—Larry Holder, New York Times, 21 June 2025
Adverb
Blazer had been wearing a wire, working in tandem with an FBI undercover, ensnaring more than ten coaches in an elaborate plot that revealed corruption in the basketball programs at Louisville, Arizona, LSU, USC and other schools.
—Guy Lawson, Rolling Stone, 24 Mar. 2024
Back at the hospital Jack tells Brady that working undercover took a lot of courage.
—Jessica Radloff, Glamour, 8 Sep. 2023
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
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American veterans and others have traveled to smaller, clandestine clinics for treatment to deal with depression, post-traumatic stress disorder and addiction.—
Eduardo Cuevas,
USA Today,
29 June 2025
-
Gi-hun, who’d found his way back in the clandestine gaming complex (situated inside a mountain on a remote island), is Player 456 again among a new round of contestants.—
Lorraine Ali,
Los Angeles Times,
28 June 2025
Adjective
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Now, after Operation Midnight Hammer, arguably one of the most perfect covert military operations in U.S. history, who could argue? Even Trump’s most ardent critics had to give him credit.—
Sun Sentinel Editorial Board,
Sun Sentinel,
28 June 2025
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This deliberately allusive narrative style enables the author to elude the topic of Nazism—or at least to hint at it in a covert way, thus making the novel acceptable to a wide German audience at the time of its publication in 1968.—
Ombline Damy,
JSTOR Daily,
26 June 2025
Noun
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For those who don't know, Area 51 is a large, secretive military base in the remote Nevada desert where several exotic military aircraft have been developed and tested over the years, including the venerable U-2 spy plane way back when.—
Jim Clash,
Forbes.com,
6 July 2025
-
Israel’s spy service conducted elaborate sabotage operations on Iranian soil.—
Nabih Bulos
Foreign Correspondent,
Los Angeles Times,
5 July 2025
Adverb
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Early evidence has shown the bombing did not reach depths necessary to destroy the facilities, which are buried deeply underground, according to a second U.S. official.—
Nicole Fallert,
USA Today,
26 June 2025
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The amount of groundwater replenishment during the 2024 water year, while significant, was less than the 8.7 million acre-feet that percolated underground during the extremely wet 2023 water year, according to state estimates.—
Ian James,
Los Angeles Times,
24 June 2025
Adjective
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Amazon’s secret outlet has more than 20,000 markdowns on summer clothing and accessories.—
Emily Weaver,
People.com,
28 June 2025
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Peter Vack This fictional tale collapses the internet, theater, and the movie screen into a dystopian world where, with the creation of a world blurring online and offline, the three merge into a secret fourth thing.—
Matt Shaw,
Forbes.com,
28 June 2025
Noun
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According to a 1996 Los Angeles Times piece, an 18th Street operative pitched his plan for taking over Orange County in a back alley in Cudahy, with two dozen associates in tow.—
Mia Cathell,
The Washington Examiner,
27 June 2025
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The Mossad, Israel’s equivalent of the CIA, had personnel in Iran ready for the launch of Operation Rising Lion, something that was revealed in unprecedented fashion when the agency released video of its operatives at work.—
Rachel Wolf , Yonat Friling,
FOXNews.com,
26 June 2025
Adjective
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With over 2,300 franchise stores across 40 countries, FAT Brands purchased the barbecue bar and grill for $30 million from Sun Capital Partners private equity in 2023.—
Claire Grant,
USA Today,
30 June 2025
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Cheng Xin | Getty Images Google on Monday announced a partnership with Commonwealth Fusion Systems, or CFS, a private company spun off from the Massachusetts Institute of Technology, which marks the tech giant′s first commercial commitment to fusion.—
Kate Dore, CFP®, EA,
CNBC,
30 June 2025
Noun
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Six crew members and a gate agent at Charlotte Douglas International Airport were taken to the hospital Friday night after inhaling something, according to MEDIC.—
Jeff A. Chamer,
Charlotte Observer,
28 June 2025
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In many cases, legacy systems can’t easily accommodate these autonomous agents without substantial reengineering.—
Sol Rashidi,
Forbes.com,
28 June 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 11 Jul. 2025.
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