Other forms: infested, infesting, infests
To infest is to fill a place in unpleasant numbers. Infested with rats, a shark-infested sea, infest the crop.
It is always unwelcome and always about numbers rather than a single animal — one rat is not an infestation. Shark-infested is a journalistic favourite and biologists dislike it, since the sharks live there. Note that the Latin infestus means hostile.
1verbinfestTo fill a place in unpleasant numbers.
“The old house was infested with mice, and we could hear them at night.”
infest is an overrunning.
Latin infestare means to attack, from infestus, hostile. The word's origin beyond that is uncertain.
Proto-Indo-European
*gʷʰen-
Latin
īnfestō — assail, molest
Old French
infester — to infest
Middle English
infesten
English, today
infest
Built from
From Middle English infesten, from Old French infester (“to infest”), from Latin īnfestō (“assail, molest”), from īnfestus (“hostile”), of uncertain origin.
Etymology from Wiktionary, CC BY-SA