go into or through (something), especially with force or effort
the shrapnel had penetrated the wall
tunnels that penetrate deep into the earth's core
gain access to (an organization, place, or system), especially when this is difficult to do
their operation had been thoroughly penetrated by foreign intelligence
hackers penetrated security firewalls
succeed in understanding or gaining insight into (something complex or mysterious)
I could never penetrate his thoughts
a magician who seemed to have penetrated the mysteries of nature