permeable (adj.) Look up permeable at Dictionary.com
early 15c., from Late Latin permeabilis "that can be passed through, passable," from Latin permeare "to pass through, go over," from per "through" (from PIE root *per- (1) "forward," hence "through") + meare "to pass," from PIE root *mei- (1) "to change, go, move." Related: Permeably.