as in treacherous
formal
causing harm in a way that is gradual or not easily noticed
Most people with this insidious disease have no idea that they are infected. an insidious enemy
Synonyms & Similar Words
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of insidious
But psychological research presents a deeper, more insidious explanation — one that doesn’t just apply to politicians and public figures, but to clinicians, as well.
—
Robert Pearl, Forbes.com, 26 May 2025
Beyond the physical abuse, Cassie endured a steady drumbeat of insidious threats that sent an unmistakable message: the violence could escalate at any moment.
—Lauren Hersh, New York Daily News, 21 May 2025
Here, though, the spectacle of Laura’s darkness is not presented as a slowly unfolding insidious revelation.
—Owen Gleiberman, Variety, 16 May 2025
And that’s indeed already happening, probably in insidious ways that aren’t publicly disclosed.
—Kieran Press-Reynolds, Pitchfork, 14 May 2025
See All Example Sentences for insidious
Robert Pearl, Forbes.com, 26 May 2025
Beyond the physical abuse, Cassie endured a steady drumbeat of insidious threats that sent an unmistakable message: the violence could escalate at any moment.
—Lauren Hersh, New York Daily News, 21 May 2025
Here, though, the spectacle of Laura’s darkness is not presented as a slowly unfolding insidious revelation.
—Owen Gleiberman, Variety, 16 May 2025
And that’s indeed already happening, probably in insidious ways that aren’t publicly disclosed.
—Kieran Press-Reynolds, Pitchfork, 14 May 2025
See All Example Sentences for insidious
Recent Examples of Synonyms for insidious
Adjective
-
The Neshaminy Creek, placid in calm weather, turns treacherous after heavy rains, such as those that fell on Bucks County in the days before his accident.—
JD Mullane,
USA Today,
29 May 2025
-
The savvy financial advisor Rick Kahler, president of Kahler Financial Group in Rapid City, S.D., tells us how to navigate this treacherous path.—
Larry Light,
Forbes.com,
27 May 2025
Adjective
-
Your new album, Faith, is a lot subtler than your debut, Signs.—
Philip Sherburne,
Pitchfork,
6 June 2025
-
The family secrets were subtle but pervasive, reverberating not just through this nuclear family, but also across generations.—
Susan Walter
June 6,
Literary Hub,
6 June 2025
Adjective
-
Social media users have wielded AI tools to create deepfakes and spread misinformation—but also to fact-check and debunk false claims.—
Andrew R. Chow,
Time,
12 June 2025
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On Wednesday, Dobbins addressed the story about his false claims.—
Jen McCaffrey,
New York Times,
12 June 2025
Adjective
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Payment providers can face significant card brand penalties if they are found to facilitate deceptive behavior.—
Rochelle Blease,
Forbes.com,
13 June 2025
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Don't fall prey to deceptive marketing language and inflated MSRP prices—our tips only take a few moments.—
Louryn Strampe,
Wired News,
12 June 2025
Adjective
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Jake Gyllenhaal is his foil as the perfidious Iago, who goads Othello into unreasoning jealousy with lies about his beloved Desdemona (Molly Osborne).—
New York Times,
New York Times,
17 Feb. 2025
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Since then, Putin has sought instead to rally the public to the defense of a motherland besieged by the perfidious and cunning West.—
Leon Aron,
The Atlantic,
5 Dec. 2024
Adjective
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Earlier this year, the company’s shareholders voted against a proposal to halt shipments of arms to Israel on the grounds that premise of the proposal was incorrect.—
Glenn Taylor,
Sourcing Journal,
13 June 2025
-
More: Biden to create two new national monuments in California The Justice Department determined an opinion from the U.S. Attorney General nearly a century ago was incorrect.—
Dinah Voyles Pulver,
USA Today,
13 June 2025
Adjective
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And then what happens when taxpayers are given the wrong answer?—
Tax Notes Staff,
Forbes.com,
10 June 2025
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For HBCUs, the moment is reminiscent of the era decades ago when Black colleges were compelled to argue that school segregation was wrong but also needed to maintain government support for their institutions, said Marybeth Gasman, a Rutgers University professor who has studied the history of HBCUs.—
Cheyanne Mumphrey,
Los Angeles Times,
9 June 2025
Cite this Entry
“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 18 Jun. 2025.
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