tr.v. in·fest·ed, in·fest·ing, in·fests
1. To inhabit or overrun in numbers or quantities large enough to be harmful, threatening, or obnoxious: rats infesting the sewers; streets that were infested with drugs.
2. To live as a parasite in or on: livestock that were infested with tapeworms.
[Middle English infesten, to distress, from Old French infester, from Latin īnfestāre, from īnfestus, hostile; see gwhedh- in the Appendix of Indo-European roots.]
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