Adj. | 1. | permeable - allowing fluids or gases to pass or diffuse through; "permeable membranes"; "rock that is permeable by water" leaky - permitting the unwanted passage of fluids or gases ; "a leaky roof"; "a leaky defense system" pervious - admitting of passage or entrance; "pervious soil"; "a metal pervious to heat" impermeable - preventing especially liquids to pass or diffuse through; "impermeable stone"; "an impermeable layer of scum"; "a coat impermeable to rain" |