- capable of being penetrated.
Origin of penetrable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for unpenetrable
early 15c., "penetrating," from Latin penetrabilis "penetrable, vulnerable," from penetrare (see penetrate). Meaning "capable of being penetrated" is attested from 1530s; figurative use by 1590s. Related: Penetrability.
Online Etymology Dictionary, © 2010 Douglas Harper