Definitions:

1. make one's way deeper into or through verb
   • The hikers did not manage to penetrate the dense forest
2. pass into or through, often by overcoming resistance verb
   • The bullet penetrated their chest.

Synonyms:

• breach
• diffuse
• Enter
• fathom
• Impale
• infiltrate
• Insinuate
• Invade
• perforate
• Permeate
• Pierce
• Puncture
• Transpierce