As an adjective impervious
is unaffected or unable to be affected by.
As a noun rockfill is
a dam's embankment of compacted free-draining granular earth, often containing rocks, with an impervious zone.
Unaffected or unable to be affected by.
, title=(The Celebrity
, passage=Although the Celebrity was almost impervious
to sarcasm, he was now beginning to exhibit visible signs of uneasiness, the consciousness dawning upon him that his eccentricity was not receiving the ovation it merited.}}
Preventive of any penetration; impenetrable, impermeable, particularly of water.
Immune to damage or effect.
A dam's embankment of compacted free-draining granular earth, often containing rocks, with an impervious zone.