(n.) The act of permeating, passing through, or spreading throughout, the pores or interstices of any substance.

brewing decoction diffusion drench drenching ducking dunking imbruement imbuement impregnation infiltration infusion injection instillation instillment interpenetration leaching lixiviation maceration marination overrunning overspreading overswarming penetration percolation pervasion pulping saturation seething soak soakage soaking sopping souse sousing steeping suffusion transfusion