Main entry: interpenetrate, permeate
Definition: penetrate mutually or be interlocked
Usage: The territories of two married people interpenetrate a lot
Main entry: diffuse, penetrate, permeate, pervade, interpenetrate, imbue, riddle
Definition: spread or diffuse through
Usage: An atmosphere of distrust has permeated this administration; music penetrated the entire building; His campaign was riddled with accusations and personal attacks