INTERPENETRATE
interpenetrate, permeate
(verb) penetrate mutually or be interlocked; “The territories of two married people interpenetrate a lot”
permeate, pervade, penetrate, interpenetrate, diffuse, imbue, riddle
(verb) spread or diffuse through; “An atmosphere of distrust has permeated this administration”; “music penetrated the entire building”; “His campaign was riddled with accusations and personal attacks”
Source: WordNet® 3.1
Etymology
Verb
interpenetrate (third-person singular simple present interpenetrates, present participle interpenetrating, simple past and past participle interpenetrated)
To penetrate mutually or reciprocally.
To permeate or pervade.
Source: Wiktionary
In`ter*pen"e*trate, v. t.
Definition: To penetrate between or within; to penetrate mutually.
It interpenetrates my granite mass. Shelley.
In`ter*pen"e*trate, v. i.
Definition: To penetrate each the other; to penetrate between bodies or
their parts. 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.
Source: Webster’s Unabridged Dictionary 1913 Edition