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insidious

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adjective in·sid·i·ous \in-ˈsi-dē-əs\

Simple Definition of insidious

  • : causing harm in a way that is gradual or not easily noticed

Source: Merriam-Webster's Learner's Dictionary

Full Definition of insidious

  1. 1 a :  awaiting a chance to entrap :  treacherous b :  harmful but enticing :  seductive <insidious drugs>

  2. 2 a :  having a gradual and cumulative effect :  subtle <the insidious pressures of modern life> b of a disease :  developing so gradually as to be well established before becoming apparent

insidiously

adverb

insidiousness

noun

Examples of insidious in a sentence

  1. But the litigation is also prompting a subtle and insidious change in the way that medicine is practiced, which affects anyone who consults a health professional, even if they would not dream of setting foot in a lawyer's office. It is known as “defensive medicine.” —Geoff Watts, New Scientist, 23–29 Oct. 2004

  2. Spin is sometimes dismissed as a simple euphemism for lying. But it's actually something more insidious: indifference to the truth. —Michael Kinsley, Time, 25 Dec. 2000–1 Jan. 2001

  3. As these boats aged and bedding compounds deteriorated, the water torture began, which led to rot, corrosion, and other insidious problems. —Ralph Naranjo, Cruising World, April 1999

  4. Most people with this insidious disease have no idea that they are infected.



Origin and Etymology of insidious

Latin insidiosus, from insidiae ambush, from insidēre to sit in, sit on, from in- + sedēre to sit — more at sit


First Known Use: 1545

Rhymes with insidious


Medical Dictionary

insidious

play
adjective in·sid·i·ous \in-ˈsid-ē-əs\

Medical Definition of insidious

  1. :  developing so gradually as to be well established before becoming apparent <an insidious disease>

insidiously

adverb



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