infiltrar

to infiltrate

verb een-feel-TRAHR Rare

Usage Note

Infiltrar (also used reflexively as infiltrarse) means to penetrate a group, organization, or substance secretly or gradually — whether a spy infiltrating a network or water seeping through soil. The reflexive infiltrarse en is the most common pattern: se infiltró en el grupo. In medicine it can also describe injecting a substance into tissue.

Examples

"El agente logró infiltrarse en la organización."

Natural Translation

The agent managed to infiltrate the organization.

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