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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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.