1. To enter into; to make way into the interior of; to effect an entrance into; to pierce; as, light penetrates darkness.
2. To affect profoundly through the senses or feelings; to touch with feeling; to make sensible; to move deeply; as, to penetrate one’s heart with pity. The translator of homer should penetrate himself with a sense of the plainness and directness of Homer’s style. (M. Arnold)
3. To pierce into by the mind; to arrive at the inner contents or meaning of, as of a mysterious or difficult subject; to comprehend; to understand. Things which here were too subtile for us to penetrate. (ray)
Origin: L. Penetratus, p.p. Of penetrare to penetrate; akin to penitus inward, inwardly, and perh. To pens with, in the power of, penus store of food, innermost part of a temple.