from
The Collaborative International Dictionary of English v.0.48
Interpenetrate \In`ter*pen"e*trate\, v. i.
To penetrate each the other; to penetrate between bodies or
their parts.
[1913 Webster]
{Interpenetrating molding} (Arch.), in late Gothic
architecture, a decoration by means of moldings which seem
to pass through solid uprights, transoms, or other
members; often, two sets of architectural members
penetrating one another, in appearance, as if both had
been plastic when they were put together.
[1913 Webster]