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
Examples Sentences
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Recent Examples of insidious
Beck and Woods don’t have to dream up something alien when these kinds of garden-variety predators are all too insidious.
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Katie Walsh, Twin Cities, 7 Nov. 2024
Insufficient sleep is the most insidious sleep problem among older children.
—Lori Miller Kase, Parents, 30 Oct. 2024
Postpartum mental illnesses can be insidious and take many different forms, but the prosecution’s depiction of Lindsay challenged the stereotypical assumptions about insanity that had seemingly informed the public’s initial sympathy.
—Eren Orbey, The New Yorker, 14 Oct. 2024
However frivolous a word like beauty may sound, beauty, as a system, is often an insidious concept.
—Essence, 5 Nov. 2024
See all Example Sentences for insidious 
Katie Walsh, Twin Cities, 7 Nov. 2024
Insufficient sleep is the most insidious sleep problem among older children.
—Lori Miller Kase, Parents, 30 Oct. 2024
Postpartum mental illnesses can be insidious and take many different forms, but the prosecution’s depiction of Lindsay challenged the stereotypical assumptions about insanity that had seemingly informed the public’s initial sympathy.
—Eren Orbey, The New Yorker, 14 Oct. 2024
However frivolous a word like beauty may sound, beauty, as a system, is often an insidious concept.
—Essence, 5 Nov. 2024
See all Example Sentences for insidious
Recent Examples of Synonyms for insidious
Adjective
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The Sunday evening and Monday morning commutes are likely to be treacherous.Raja Krishnamoorthi, Newsweek, 15 Dec. 2024
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Hawai`i’s statehood itself results from a treacherous cabal of business interests–Dole among them–conspiring together on a scheme to wrest control of the land away from Native Hawaiians and give it the U.S.Chadd Scott, Forbes, 15 Dec. 2024
Adjective
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The palate has a mix of caramel, cinnamon sugar, and subtle spice, which offers a rich, layered experience.Maggie Menderski, The Courier-Journal, 14 Dec. 2024
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The Cognac is complex, featuring plum, fig, and licorice notes, a rich, spicy finish, and subtle vanilla undertones.Joseph V Micallef, Forbes, 14 Dec. 2024
Adjective
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Best travel insurance policies Truth or false:There more flight disruptions during the holidays?Kathleen Wong, USA TODAY, 8 Dec. 2024
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Meanwhile, Hunter Biden was convicted of lying on a federal form about his drug use to purchase a revolver, submitting a false statement into a federal record, and unlawfully possessing the firearm for 11 days.Jenny Goldsberry, Washington Examiner - Political News and Conservative Analysis About Congress, the President, and the Federal Government, 8 Dec. 2024
Adjective
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Lilly has sent cease-and-desist letters to numerous compounding sellers, and both companies have filed lawsuits against numerous compounding pharmacies, alleging trademark infringement and deceptive marketing.Bob Woods, CNBC, 8 Dec. 2024
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Yes, but: Brandi Tuck, executive director of the nonprofit Path Home, has been working with homeless families for nearly two decades and says those numbers are likely deceptive undercounts.Kale Williams, Axios, 6 Dec. 2024
Adjective
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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
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And in this new era of Sino-Western rivalry, the Olympics are also used by more nationalistic elements of the Chinese media as a way to portray China in a positive light against the perfidious Americans and Europeans.Alexander Smith, NBC News, 11 Aug. 2024
Adjective
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The toy maker advised parents that the label was incorrect and directed consumers who had already purchased the product to discard its packaging and contact Mattel Customer Service.Stacy Perman, Los Angeles Times, 5 Dec. 2024
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But an incorrect response loses any points the team might’ve already gained from this clue, and another team is allowed to steal.Devon Ivie, Vulture, 5 Dec. 2024
Adjective
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Six people, including two children, are dead after a person driving a pickup truck the wrong way on a Mississippi highway collided with a car.Charlotte Phillipp, People.com, 8 Dec. 2024
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There are many reasons why Donald Trump is wrong about tariffs.John Gustavsson, National Review, 7 Dec. 2024
Thesaurus Entries Near insidious
Cite this Entry
“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 21 Dec. 2024.
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