im·per·vi·ous 
/ɪmˈpɚvijəs/ adjective
/ɪmˈpɚvijəs/ adjective [more impervious; most impervious] 1 technical : not allowing something (such as water or light) to enter or pass through — usually + to ▪ a substance impervious to light ▪ a coat impervious to rain 2 formal : not bothered or affected by something — usually + to ▪ He seems impervious to criticism.
— im·per·vi·ous·ness noun [noncount]
