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
Synonyms & Similar Words
Antonyms & Near Antonyms
Example Sentences
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Recent Examples of undercover
Thomas Brewster, Forbes.com, 3 June 2025
Quiet Skies, which began in 2010, employs analysts and undercover air marshals to monitor people in airports and during flights, using outstanding warrants, facial recognition software, identification of suspicious travel patterns and behaviors and other data to try to prevent terrorist attacks.
—Jennifer Jacobs, CBS News, 3 June 2025
Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Adjective
He was caught out by undercover agents posing as interested parties, according to the DOJ.
—Thomas Brewster, Forbes.com, 3 June 2025
Quiet Skies, which began in 2010, employs analysts and undercover air marshals to monitor people in airports and during flights, using outstanding warrants, facial recognition software, identification of suspicious travel patterns and behaviors and other data to try to prevent terrorist attacks.
—Jennifer Jacobs, CBS News, 3 June 2025
Noun
Back at the hospital Jack tells Brady that working undercover took a lot of courage.
—Jessica Radloff, Glamour, 8 Sep. 2023
The documentary is a first time collaboration between ABC News Studios and the Associated Press following a former Army sniper undercover inside the KKK.
—ABC News, 30 Apr. 2023
See All Example Sentences for undercover
Recent Examples of Synonyms for undercover
Adjective
-
Syria under Assad is believed to have operated an extensive clandestine nuclear program, which included an undeclared nuclear reactor built by North Korea in eastern Deir el-Zour province.—
Arkansas Online,
Arkansas Online,
5 June 2025
-
The only way to pre-empt detection by these IAEA watchdogs would be for Ukraine to withdraw from the nuclear Non-Proliferation Treaty and expel the atomic inspectors, but those moves would amount to trumpeting Kyiv’s clandestine quest to develop a nuclear warhead.—
Kevin Holden Platt,
Forbes.com,
1 June 2025
Adjective
-
Striking Iran’s nuclear program would likely set off a much larger conflict in which Israel and the United States hunt for covert Iranian nuclear sites and Tehran retaliates in the Middle East and beyond.—
Richard Nephew,
Foreign Affairs,
26 May 2025
-
Mon Mothma's speech Mon Mothma's covert support of the Rebels becomes public following the devastating events of the Ghorman Massacre.—
Nick Romano,
EW.com,
25 May 2025
Noun
-
North Korea has repeatedly failed to launch military spy satellites.—
Choe Sang-Hun,
New York Times,
31 May 2025
-
This was a real group of spies that pretended to be Southern and infiltrated the South and became friends and colleagues.—
Brayden Garcia,
Fort Worth Star-Telegram,
29 May 2025
Adverb
-
The French then moved their bomb tests underground to In Ekker, further east in Algeria.—
Matthew Wills,
JSTOR Daily,
2 June 2025
-
The carbon can then be reused or injected deep underground where it will be naturally transformed into stone, locking it up permanently.—
Laura Paddison,
CNN Money,
30 May 2025
Adjective
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There’s no bouncer who will listen to you whisper a secret word, but rather, a key card that scans you in.—
Ella Gonzales,
Fort Worth Star-Telegram,
4 June 2025
-
Rumors of secret deals and under-the-table payments have circulated for years.—
Arkansas Online,
Arkansas Online,
4 June 2025
Noun
-
Ashman, a 23-year-old water operative from Stafford, was one of two suspects questioned about the incident.—
Armando Tinoco,
Deadline,
3 June 2025
-
Senior Hamas operatives with British citizenship have established charitable foundations that raise millions of pounds annually, some of which ends up in the hands of the group’s military wing.—
Efrat Lachter,
FOXNews.com,
1 June 2025
Adjective
-
Back in August 1993, an eight-year-old Harry, along with his older brother Prince William, then 11, enjoyed a private visit to Walt Disney World in Florida with Princess Diana.—
Madison E. Goldberg,
People.com,
7 June 2025
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Redstone kept her diagnosis private, sharing it with only a tight circle of relatives, close friends, and advisers including David Ellison, the Skydance head and tech heir, whose company is set to purchase Paramount and the Redstone family’s stake, NYT added.—
Reuters,
NBC news,
6 June 2025
Noun
-
The writer’s death on June 3 was confirmed by his husband, Michael Carroll, and agent Bill Clegg, The New York Times, The Guardian and NBC News report.—
Carly Tagen-Dye,
People.com,
4 June 2025
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These agents learn from interactions, adapting responses for a more human-like experience, reducing wait times and ensuring consistent service quality. CNN reports that tech companies are introducing early AI agent offerings.—
Pradeep Kumar Muthukamatchi,
Forbes.com,
4 June 2025
Cite this Entry
“Undercover.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undercover. Accessed 11 Jun. 2025.
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