Penetrate
Part of speech: verb
Definition: Manage to enter into. To insert a penis into an opening, such as a vagina.
Example sentence: I think Buddhism should open the door of psychology and healing to penetrate more easily into the Western world.
Infiltrate
Part of speech: verb
Definition: To surreptitiously penetrate, enter or gain access.To cause a fluid to pass through a substance by filtration.To send soldiers through gaps in the enemy line.
Example sentence: Any time that we read a script and the 'Leverage' team has to infiltrate a place, assume identities, or become con artists ourselves to take down the really bad con artists, it's always fun to do that.