adjective. Impossible to permeate.

Not permeable; not permitting the passage of a fluid (especially water) through its substance.

adjective. Not permeable; not permitting passage, as of a fluid. through its substance; impervious; impenetrable.

adjective. impossible to permeate

adjective. not allowing passage, especially of liquids; waterproof

adjective. preventing especially liquids to pass or diffuse through

"On the wall hung a simple chart of a rock formation with layers labelled impermeable, source, permeable and reservoir; a list saying things like spudded Oct. '71, plugged and abandoned Jan.' 72; and three brightly coloured maps of the North Sea, each of them showing a different aspect of the oil drilling operations going on there."

permeable  

nonpermeable  permeability  

retentive  water-repellent  water-resistant  

air-tight  alluvial  bituminous  calcareous  clayey  

close  close-knit  close-textured  close-woven  closed