1. To enter into; to make way into the interior of; to pierce.
    Light penetrates darkness.
  2. To achieve understanding of, despite some obstacle; to comprehend; to understand.
    I could not penetrate Burke's opaque rhetoric.
  3. To affect profoundly through the senses or feelings; to move deeply.
    to penetrate one's heart with pity
  4. To infiltrate an enemy to gather intelligence.
  5. To insert the penis into an opening, such as a vagina or anus.

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