1. Not admitting of passage or capable of being affected
   "a material impervious to water"; "someone impervious to argument"
   - imperviable

See also: acid-fast, colorfast [US], colourfast [Brit, Cdn], corrosion-resistant, fast, greaseproof, impermeable, imperviousness, ladder-proof, mothproof, moth-resistant, proof, resistant, rot-resistant, runproof, run-resistant, soundproof

Antonym: pervious

• Lancelot
• lanceolate
• lanceolate leaf
• lanceolate spleenwort
• lancer
• lancers
• lancet
• lancet arch
• lancet window
• lancet-shaped
• lancetfish
• lancewood
• lancewood tree
• Lanchou
• Lanchow
• lancinate
• lancinating
• land
• land agent
• land area
• land cress
• land development
• land grant
• land mile
• land mine