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
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Example Sentences
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Recent Examples of insidious
Another insidious provision would allow any voter anywhere in the state to challenge an initiative’s placement after the Supreme Court has approved it, and again even after voters ratify it.
—
Orlando Sentinel and South Florida Sun Sentinel Editorial Boards, Orlando Sentinel, 27 Jan. 2025
In it, a fantastical ancient Asian Empire is on the verge of destruction, torn apart by insidious rivalry.
—Nellie Andreeva, Deadline, 22 Jan. 2025
Daniel Kaluuya stars as a Black photographer visiting his white girlfriend's parents and is terrified to discover the truly insidious reason for his invitation.
—Brian Truitt, USA TODAY, 22 Jan. 2025
The War from Within The most insidious aspect of South Africa’s wildlife war goes beyond the sheer number of animals killed to the number of people with a hand in the killing.
—Dac Collins, Outdoor Life, 16 Jan. 2025
See all Example Sentences for insidious 
Orlando Sentinel and South Florida Sun Sentinel Editorial Boards, Orlando Sentinel, 27 Jan. 2025
In it, a fantastical ancient Asian Empire is on the verge of destruction, torn apart by insidious rivalry.
—Nellie Andreeva, Deadline, 22 Jan. 2025
Daniel Kaluuya stars as a Black photographer visiting his white girlfriend's parents and is terrified to discover the truly insidious reason for his invitation.
—Brian Truitt, USA TODAY, 22 Jan. 2025
The War from Within The most insidious aspect of South Africa’s wildlife war goes beyond the sheer number of animals killed to the number of people with a hand in the killing.
—Dac Collins, Outdoor Life, 16 Jan. 2025
See all Example Sentences for insidious
Recent Examples of Synonyms for insidious
Adjective
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Being a woman on this show has always been more treacherous than Miss Patricia’s one loop around the block in her Rolls-Royce.—
Brian Moylan,
Vulture,
6 Feb. 2025
-
Snowfall is expected to accumulate between 6 and 12 inches in eastern parts of the state, with Omaha and Lincoln experiencing treacherous conditions.—
Thomas G. Moukawsher,
Newsweek,
5 Feb. 2025
Adjective
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China reacted angrily Monday to new State Department wording that appeared to indicate a subtle shift in favor of Taipei.—
Christian Shepherd The Washington Post,
arkansasonline.com,
18 Feb. 2025
-
This style can be easily individualized with soft braids, details creating a subtle crown effect.—
Calin Van Paris,
Vogue,
18 Feb. 2025
Adjective
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In the Burrow case, the suspects allegedly carried bogus ID cards purportedly from Argentina and other countries, and bearing false names, according to the affidavit.—
Bill Chappell,
NPR,
11 Feb. 2025
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There’s a lot of false symbolism and false activism, and there’s a lot of people who really capitalize on this half-baked symbolism without deliverables.—
Charisma Madarang,
Rolling Stone,
11 Feb. 2025
Adjective
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It’s got a slim, high-rise fit with a deceptive amount of cargo space that includes tennis ball pockets and side pockets.—
Clint Davis,
People.com,
10 Feb. 2025
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Phishing campaigns leverage compromised accounts or domains to send deceptive invitations, luring victims into downloading harmful files.—
Kurt Knutsson, CyberGuy Report,
Fox News,
10 Feb. 2025
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
-
Many of those who have lost insurance missed form deadlines or had an incorrect address, while others no longer met the eligibility criteria.—
Josh Hammer,
Newsweek,
14 Feb. 2025
-
Wednesday's edition included incorrect information about King's votes.—
Tony Holt,
arkansasonline.com,
13 Feb. 2025
Adjective
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But to not be able to talk and think about health without understanding the undercurrent of social factors impacting our health is wrong.—
Justin Gest,
Newsweek,
11 Feb. 2025
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Still, experts say there’s nothing wrong with enjoying chocolate in moderation.—
Elizabeth Yuko,
Health,
11 Feb. 2025
Thesaurus Entries Near insidious
Cite this Entry
“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 21 Feb. 2025.
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