Impervious/ɪmˈpɜːrviəs/ Definition 1 of 2Pro Tip 1/3Literal Barrier Used when something physically stops another substance from passing through. The gloves were impervious to the chemicals. Pro Tip 2/3Technical Context Often found in descriptions of materials in science, construction, or technology. They used an impervious membrane beneath the road. Pro Tip 3/3Nature Proof Suggests resistance to natural elements like water, heat, and humidity. Our tent is impervious to rain.