1. graded adjective & adjective [usu v-link ADJ]
If you are impervious to someone's actions, you are not affected or influenced by them. [+ to] ⇒ She seems almost impervious to the criticism from all sides. ⇒ The political system there has been impervious to all suggestions of change.
2. adjective Something that is impervious to water, heat, or a particular object is able to resist it or stop it passing through it. [+ to] ⇒ The floorcovering you select will need to be impervious to water. ⇒ ...a layer of impervious rock.
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