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in·ter·pen·e·trate [in-ter-pen-i-treyt]

–verb (used with object)
1.
to penetrate thoroughly; permeate.
2.
to penetrate with (something else) mutually or reciprocally.

–verb (used without object)
3.
to penetrate between things or parts.
4.
to penetrate each other.


"interpenetrate." Dictionary.com Unabridged (v 1.1). Random House, Inc. 27 Jan. 2007. http://dictionary.reference.com/browse/interpenetrate>