This is the 12038th most frequent Spanish word.
infiltrado
"Infiltrado" means "infiltrated" or "a person who has secretly entered a group or organization."
Here, "infiltrado" is used to describe the action of secretly entering an area or group to gain information.
El espía se infiltró en la organización secreta.
The spy infiltrated the secret organization.
In this sentence, "infiltrado" refers to a person who has secretly entered a group or organization for covert activities.
Había un infiltrado entre los empleados que pasaba información a la competencia.
There was an infiltrator among the employees who was passing information to the competition.
Here, "infiltrado" is used in a physical context, describing how a substance (water) penetrates a solid structure.