ENGLISH
REFERENCE

infested

adj.
B2 Upper Intermediate US //ˌɪnˈfɛstɪd// UK //ɪnfˈɛstɪd// in·fest·ed

adj. full of something unpleasant or dangerous, like insects, rats, or weeds.

adj. present in large numbers so as to be unpleasant, harmful, or dangerous. A participial adjective often used predicatively after 'be' or 'become'.


SIMPLE

The old kitchen was infested with ants.

CONTEXTUAL

After the flood, the abandoned basement became infested with mold and mosquitoes.

COMPLEX

The local authorities warned that the lake had become infested with invasive weeds that were choking the native ecosystem and preventing recreational boating.

Synonyms
Usage

Typically takes the preposition 'with' followed by the source of the problem.

Pitfall

The house was infested of cockroaches.The house was infested with cockroaches.Infested requires the preposition 'with' rather than 'of' or 'by'.

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