Dictionary.com
definitions

impervious

[im-pur-vee-uhs]
|
SEE MORE SYNONYMS FOR impervious ON THESAURUS.COM

adjective

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.

RELATED WORDS

impenetrable, resistant, invulnerable, inaccessible, immune, unmoved, unaffected, impassable, hermetic, impassive, impermeable, sealed, tight, unapproachable, unreceptive, watertight
Also im·per·vi·a·ble [im-pur-vee-uh-buhl] /ɪmˈpɜr vi ə bəl/.

Origin of impervious

From the Latin word impervius, dating back to 1640–50. See im-2, pervious
Related formsim·per·vi·ous·ly, adverbim·per·vi·ous·ness, noun
Can be confusedimpermeable impervious

Synonyms for impervious

SEE MORE SYNONYMS FOR impervious ON THESAURUS.COM
3. invulnerable, closed.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for impervious

impervious

imperviable

adjective

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 Formsimperviously, adverbimperviousness, 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
Word Origin and History for impervious
adj.

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