infiltration
infiltrate + -ation
https://gyazo.com/c6e33d5704f2783a97ecb59da4cab8c7
source: Porosity, Permeability, Perviousness and Infiltration – Invisible Structures
noun
1. the action of entering or gaining access to an organization or place surreptitiously, especially in order to acquire secret information or cause damage:
潜入(行為)
e.g. the army fenced parts of the border in an effort to stop militant infiltration
e.g. cross-border infiltrations.
Medicine the spread of a tumor, cells, etc. into a tissue or organ:
浸潤
e.g. swelling of the lymph nodes due to infiltration of cancerous cells.
2. permeation of a liquid into something by filtration:
浸透
e.g. improved water infiltration into the soil
e.g. this mosaic was in danger of being lost because of the infiltration of rainwater.
3. the process of gradually permeating or becoming a part of something:
e.g. the gradual infiltration of Boyce's music into the national consciousness.