Infiltrate is defined as to pass through gaps, particularly into enemy lines or in the case of liquid passing through a substance.(verb)
An example of to infiltrate is for an army to pass through weak points in the enemy's line and seize the enemy's city.
See infiltrate in Webster's New World College Dictionary
Origin: in- + filtrate
See infiltrate in American Heritage Dictionary 4
verb in·fil·trat·ed, in·fil·trat·ing, in·fil·trates verb, transitive
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