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[im-pur-vee-uh s] /ɪmˈpɜr vi əs/
not permitting penetration or passage; impenetrable:
The coat is impervious to rain.
incapable of being injured or impaired:
impervious to wear and tear.
incapable of being influenced, persuaded, or affected:
impervious to reason; impervious to another's suffering.
Also, imperviable
[im-pur-vee-uh-buh l] /ɪmˈpɜr vi ə bəl/ (Show IPA)
Origin of impervious
1640-50; < Latin impervius. See im-2, pervious
Related forms
imperviously, adverb
imperviousness, noun
Can be confused
impermeable, impervious.
3. invulnerable, closed. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for impervious
  • They contained everything that was needed to support life underground and were virtually impervious to enemy infiltration.
  • Peptides still appeared utterly impervious to all the new mechanisms of resistance that bacteria had employed.
  • We have already established that certain people here are impervious to logic.
  • These structures are often stable and impervious to meteor impacts.
  • And as tough as they can be, the immune systems of doctors and nurses are not impervious to influenza.
  • Vaccine fear is an intrinsic reflection of the subjective nature of risk perception, and in some cases impervious to information.
  • impervious surfaces, or surfaces that can't absorb water, increase runoff.
  • Roads, sidewalks, and parking lots are impervious surfaces.
  • But not even paradise is impervious to the changing global environment.
  • In a short time you'll be doing unholy stunts that you once concluded were impervious.
British Dictionary definitions for impervious


not able to be penetrated, as by water, light, etc; impermeable
(often postpositive) foll by to. not able to be influenced (by) or not receptive (to): impervious to argument
Derived Forms
imperviously, adverb
imperviousness, noun
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
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Word Origin and History for impervious

1640s, from Latin impervius "that cannot be passed through," from assimilated form of in- "not, opposite of" (see in- (1)) + pervius "letting things through," from per "through" + via "road." Related: Imperviously; imperviousness.

Online Etymology Dictionary, © 2010 Douglas Harper
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