Medical Definition of penetrate
transitive verb: to pass into or through <enzymes that help the sperm penetrate the zona pellucida—Anna Maria Gillis>
2: to insert the penis into the vagina of in copulation
intransitive verb: to pass, extend, pierce, or diffuse into or through something <penetrating percutaneous nephroscopy or ureteroscopy—R. A. Riehle et al>
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