Infiltration
- The process of entering or gaining access to an organization or place surreptitiously, especially in order to acquire secret information or cause damage. nounThe spy's infiltration of the enemy base was crucial to the success of the mission.The company was concerned about the infiltration of their network by hackers.
- The process by which a liquid, such as water, permeates or passes through a substance or surface, often into the ground. nounThe infiltration of rainwater into the soil helps to replenish groundwater supplies.Engineers studied the infiltration rates of different soil types to improve drainage systems.