- 1[transitive, intransitive] to enter or make somebody enter a place or an organization secretly, especially in order to get information that can be used against it infiltrate something The headquarters had been infiltrated by enemy spies. infiltrate somebody into something Rebel forces were infiltrated into the country. infiltrate into something The CIA agents successfully infiltrated into the terrorist organizations. See related entries: Terrorism
- 2[intransitive, transitive] infiltrate (into) something (specialist) (especially of liquids or gases) to pass slowly into something Only a small amount of the rainwater actually infiltrates into the soil. Word Origin Middle English (as infiltration): from in- + filtrate.
BrE BrE//ˈɪnfɪltreɪt//; NAmE NAmE//ˈɪnfɪltreɪt//Verb Forms present simple I / you / we / they infiltrate
BrE BrE//ˈɪnfɪltreɪt//; NAmE NAmE//ˈɪnfɪltreɪt//he / she / it infiltrates
BrE BrE//ˈɪnfɪltreɪts//; NAmE NAmE//ˈɪnfɪltreɪts//past simple infiltrated
BrE BrE//ˈɪnfɪltreɪtɪd//; NAmE NAmE//ˈɪnfɪltreɪtɪd//past participle infiltrated
BrE BrE//ˈɪnfɪltreɪtɪd//; NAmE NAmE//ˈɪnfɪltreɪtɪd//-ing form infiltrating
BrE BrE//ˈɪnfɪltreɪtɪŋ//; NAmE NAmE//ˈɪnfɪltreɪtɪŋ//Terrorism