Dictionary
im•pen•e•tra•bil•i•ty
Pronunciation: (im-pen"i-tru-bil'i-tē, im"pen-), [key]—
n.
1. the state or quality of being impenetrable.
2. Physics.that property of matter by virtue of which two bodies cannot occupy the same space simultaneously.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.