[ in-fil-trey-ter, in-fil-trey-, ]
/ ˈɪn fɪlˌtreɪ tər, ɪnˈfɪl treɪ-, /
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See synonyms for: infiltrator / infiltrators on Thesaurus.com

Definition of infiltrator

a soldier, intelligence agent, or other person who moves surreptitiously and gradually into an organization, territory, community, or the like, especially with hostile intent:Using a false name, the infiltrator participated in meetings and prep sessions with the protest group and had complete access to their documentation.
a person or thing that causes one substance to pass into another by filtering:The roots of wetland plants serve as massive water infiltrators, allowing more rainwater to seep into the soil and recharge underground aquifers.
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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.

Origin of infiltrator

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use infiltrator in a sentence