Dictionary
im•per•me•a•ble
Pronunciation: (im-pûr'mē-u-bul), [key]—
adj.
1. not permeable; impassable.
2. Chem., Geol.(of porous substances, rocks, etc.) not permitting the passage of a fluid through the pores, interstices, etc.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.