insidious


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insidious

progressing inconspicuously but harmfully: an insidious disease; treacherous; crafty; stealthily deceitful: an insidious agreement; corrupting; cunning, wily
Not to be confused with:
invidious – unfairly discriminating; injurious; hateful; calculated to give offense; causing animosity or resentment: an invidious comment
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree

in·sid·i·ous

 (ĭn-sĭd′ē-əs)
adj.
1. Working or spreading harmfully in a subtle or stealthy manner: insidious rumors; an insidious disease.
2. Intended to entrap; treacherous: insidious misinformation.
3. Beguiling but harmful; alluring: insidious pleasures.

[From Latin īnsidiōsus, from īnsidiae, ambush, from īnsidēre, to sit upon, lie in wait for : in-, in, on; see in-2 + sedēre, to sit; see sed- in Indo-European roots.]

in·sid′i·ous·ly adv.
in·sid′i·ous·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

insidious

(ɪnˈsɪdɪəs)
adj
1. stealthy, subtle, cunning, or treacherous
2. working in a subtle or apparently innocuous way, but nevertheless deadly: an insidious illness.
[C16: from Latin insidiōsus cunning, from insidiae an ambush, from insidēre to sit in; see insessorial]
inˈsidiously adv
inˈsidiousness n
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

in•sid•i•ous

(ɪnˈsɪd i əs)

adj.
1. intended to entrap or beguile: an insidious plan.
2. stealthily treacherous or deceitful: an insidious enemy.
3. operating or proceeding inconspicuously but with grave effect: an insidious disease.
[1535–45; < Latin insidiōsus deceitful, derivative of insidi(ae) (pl.) an ambush, derivative of insidēre to sit in or on]
in•sid′i•ous•ly, adv.
in•sid′i•ous•ness, n.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.insidious - beguiling but harmful; "insidious pleasures"
seductive - tending to entice into a desired action or state
2.insidious - intended to entrap
dangerous, unsafe - involving or causing danger or risk; liable to hurt or harm; "a dangerous criminal"; "a dangerous bridge"; "unemployment reached dangerous proportions"
3.insidious - working or spreading in a hidden and usually injurious way; "glaucoma is an insidious disease"; "a subtle poison"
harmful - causing or capable of causing harm; "too much sun is harmful to the skin"; "harmful effects of smoking"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

insidious

Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002
Translations

insidious

[ɪnˈsɪdɪəs] ADJinsidioso
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

insidious

[ɪnˈsɪdiəs] adjinsidieux/euse
Collins English/French Electronic Resource. © HarperCollins Publishers 2005

insidious

adj, insidiously
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

insidious

[ɪnˈsɪdɪəs] adjinsidioso/a
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

in·sid·i·ous

a. insidioso-a, rel. a una enfermedad que se desarrolla gradualmente sin producir síntomas obvios.
English-Spanish Medical Dictionary © Farlex 2012
References in classic literature ?
Verily, with insidious beauty do sea and life gaze upon me round about:
The conditions fostering the growth of that supreme, alive excellence, as well in work as in play, ought to be preserved with a most careful regard lest the industry or the game should perish of an insidious and inward decay.
They were designed for winter wear, when treacherous drafts came down chimneys and insidious currents of deadly cold found their way through key-holes.
If in the neighborhood of your camp there should be any hilly country, ponds surrounded by aquatic grass, hollow basins filled with reeds, or woods with thick undergrowth, they must be carefully routed out and searched; for these are places where men in ambush or insidious spies are likely to be lurking.
They cooked their meat before they ate it and they shunned many articles of food as unclean that Tarzan had eaten with gusto all his life and so insidious is the virus of hypocrisy that even the stalwart ape-man hesitated to give rein to his natural longings before them.
Or did there lurk in her the insidious unhealthfulness of unwomanliness?
With the same insidious views, they now seduced the members from the league, by representing to their pride the violation it committed on their sovereignty.
Let us rather no longer insult them with the supposition that they can ever reduce themselves to the necessity of making the experiment, by a blind and tame submission to the long train of insidious measures which must precede and produce it.
There was scrub and long grass all about us, and I did not feel safe from their insidious approach.
Weeks had listened politely, with smiling modesty, till Hayward finished; then he asked one or two insidious questions, so innocent in appearance that Hayward, not seeing into what a quandary they led him, answered blandly; Weeks made a courteous objection, then a correction of fact, after that a quotation from some little known Latin commentator, then a reference to a German authority; and the fact was disclosed that he was a scholar.
And right here was John Barleycorn getting me in a more insidious though no less deadly way than when he nearly sent me out with the tide.
Could they be other than the insidious whispers of the bad angel, who would fain have persuaded the struggling woman, as yet only half his victim, that the outward guise of purity was but a lie, and that, if truth were everywhere to be shown, a scarlet letter would blaze forth on many a bosom besides Hester Prynne's?