airtight ballproof bombproof bulletproof burglarproof corrosionproof dampproof fire-resisting fireproof flameproof foolproof hermetic holeproof impassable impenetrable impermeable impervious impervious to leakproof noiseproof nonpuncturable proof proof against resistant rustproof shatterproof shellproof soundproof tight unpassable unperforable unpierceable watertight weatherproof