Verb

• S: (v) penetrate, perforate (pass into or through, often by overcoming resistance) "The bullet penetrated her chest"
• S: (v) penetrate, fathom, bottom (come to understand)
• S: (v) click, get through, dawn, come home, get across, sink in, penetrate, fall into place (become clear or enter one's consciousness or emotions) "It dawned on him that she had betrayed him"; "she was penetrated with sorrow"
• S: (v) infiltrate, penetrate (enter a group or organization in order to spy on the members) "The student organization was infiltrated by a traitor"
• S: (v) penetrate (make one's way deeper into or through) "The hikers did not manage to penetrate the dense forest"
• S: (v) penetrate (insert the penis into the vagina or anus of) "Did the molester penetrate the child?"
• S: (v) permeate, pervade, penetrate, interpenetrate, diffuse, imbue, riddle (spread or diffuse through) "An atmosphere of distrust has permeated this administration"; "music penetrated the entire building"; "His campaign was riddled with accusations and personal attacks"

Adjective

• S: (adj) acute, discriminating, incisive, keen, knifelike, penetrating, penetrative, piercing, sharp (having or demonstrating ability to recognize or draw fine distinctions) "an acute observer of politics and politicians"; "incisive comments"; "icy knifelike reasoning"; "as sharp and incisive as the stroke of a fang"; "penetrating insight"; "frequent penetrative observations"
• S: (adj) penetrative, penetrating (tending to penetrate; having the power of entering or piercing) "a toxic penetrative spray applied to the surface"; "a cold penetrating wind"; "a penetrating odor"