infestation
n. C / Un. the presence of a large number of pests, like insects or rats, in a place where they cause damage or health problems.
n. the state of being invaded or overrun by pests or parasites in numbers large enough to be harmful or obnoxious.
The landlord had to deal with a serious ant infestation.
Health inspectors closed the restaurant immediately after discovering a severe rodent infestation in the dry storage area.
Agricultural experts warned that the locust infestation could devastate the region's wheat crops if containment measures were not implemented before the next breeding cycle.
From Middle French infestation, from Late Latin infestatio. Morphologically infest + -ation.
Uncountable when referring to the general state of being infested; countable when referring to a specific instance or occurrence.