infiltrate

intransitive verb

To pass (troops, for example) surreptitiously into enemy-held territory.

intransitive verb

To penetrate with hostile intent.

intransitive verb

To enter or take up positions in gradually or surreptitiously, as for purposes of espionage or takeover.

intransitive verb

To cause (a liquid, for example) to permeate a substance by passing through its interstices or pores.

intransitive verb

To permeate (a porous substance) with a liquid or gas.

intransitive verb

To gain entrance gradually or surreptitiously.

noun

One that infiltrates, especially an abnormal substance that accumulates gradually in cells or body tissues.

To pass by filtration; percolate through pores or interstices.

To pass into or through the pores or interstices of; filter into or through.