1. the action of entering or gaining access to an organization or place secretly, especially to acquire information or cause damage
2. the process by which water on the ground surface enters the soil
Usage: geology; hydrology
3. the gradual entry or spread of something into an area where it is not wanted

Examples

• The spy’s infiltration of the enemy organization took months of careful planning.
• Security was increased to prevent terrorist infiltration of the building.
• Heavy rainfall caused rapid water infiltration into the soil.
• The infiltration rate varies depending on soil type and moisture content.
• There was concern about the infiltration of extremist ideas into the community.
• The company worked to stop the infiltration of counterfeit products into their supply chain.