1. (

• infiltrate ,

) cause (a liquid) to enter by penetrating the interstices ;

2. (

• infiltrate ,
• penetrate

) enter a group or organization in order to spy on the members; "The student organization was infiltrated by a traitor" ;

3. (

• infiltrate ,

) pass into or through by filtering or permeating; "the substance infiltrated the material" ;

4. (

• infiltrate ,
• pass_through ,

) pass through an enemy line; in a military conflict ;