Infiltration /(?)/

In·fil·tra·tion

Infiltration

n.
  1. The act or process of infiltrating, as of water into a porous substance, of a fluid into the cells of an organ or part of the body, or of persons into a hostile organization.
  2. The substance which has entered the pores or cavities of a body.
    Calcareous infiltrations filling the cavities.
    — Kirwan.

Phrases & Compounds
Fatty infiltration
See under Fatty.
Infiltration gallery
a filter gallery.