insidious
[ in-sid-ee-uhs ]
/ ɪnˈsɪd i əs /
adjective
intended to entrap or beguile: an insidious plan.
stealthily treacherous or deceitful: an insidious enemy.
operating or proceeding in an inconspicuous or seemingly harmless way but actually with grave effect: an insidious disease.
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Nearby words
inside track, inside track, the, insider, insider dealing, insider trading, insidious, insight, insightful, insigne, insignia, insignificance
Origin of insidious
Related forms
Can be confused
insidious invidiousDictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for insidious
British Dictionary definitions for insidious
insidious
/ (ɪnˈsɪdɪəs) /
adjective
stealthy, subtle, cunning, or treacherous
working in a subtle or apparently innocuous way, but nevertheless deadlyan insidious illness
Derived Forms
insidiously, adverbinsidiousness, nounWord Origin for insidious
C16: from Latin insidiōsus cunning, from insidiae an ambush, from insidēre to sit in; see insessorial
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medicine definitions for insidious
insidious
[ ĭn-sĭd′ē-əs ]
adj.
Being a disease that progresses with few or no symptoms to indicate its gravity.
Related forms
in•sid′i•ous•ly adv.The American Heritage® Stedman's Medical Dictionary
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