infested
B2Neutral to Formal. Often used in news, academic, and technical writing about pests/diseases. Can be informal in hyperbolic expressions.
Definition
Meaning
Overrun or plagued by large numbers of pests, parasites, or harmful things, typically causing damage or nuisance.
Used metaphorically to describe being overwhelmed or overrun by something undesirable or harmful, such as crime, corruption, or errors.
Linguistics
Semantic Notes
Implies a negative, invasive presence in large numbers. The word often carries connotations of disgust, danger, or a loss of control over the environment. It's used both literally (with organisms) and figuratively.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning. British English may slightly favour 'infested with', while American English uses both 'infested with' and 'infested by'.
Connotations
Identical negative connotations in both varieties.
Frequency
Comparatively similar frequency in both dialects.
Vocabulary
Collocations
Grammar
Valency Patterns
[place/thing] be/become infested with [pest/thing][pest/thing] infest [place/thing]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “Rat-infested dump (metaphor for a terrible place)”
- “Bug-infested code (tech: software full of errors)”
Usage
Context Usage
Business
Rare. Possibly in hospitality/real estate: 'The property was unsellable due to being infested.'
Academic
Common in biology, public health, and history texts: 'The trenches were infested with lice.'
Everyday
Common when discussing pests at home or in nature: 'Our picnic was ruined by an ant-infested blanket.'
Technical
Specific in agriculture, entomology, and medicine: 'The sample was infested with Cryptosporidium parvum.'
Examples
By Part of Speech
verb
British English
- The old mattress was thrown out after it became infested.
- The warehouse has been infested by pigeons.
American English
- They had to tent the house after termites infested it.
- The creek is infested with mosquitos in summer.
adverb
British English
- N/A - 'infested' is not used as an adverb.
American English
- N/A - 'infested' is not used as an adverb.
adjective
British English
- They abandoned the infested flat.
- We had to dispose of the infested grain.
American English
- Stay out of that infested barn.
- The code was bug-infested and unstable.
Examples
By CEFR Level
- The old house was full of mice.
- I don't like that dirty place.
- The kitchen was infested with cockroaches.
- They left the campsite because it was infested with ants.
- The historic documents were found in a rat-infested basement.
- Public health officials cleared the infested tenement building.
- The once-pristine coral reef is now infested with invasive crown-of-thorns starfish.
- The report described a bureaucracy infested with corruption and nepotism.
Learning
Memory Aids
Mnemonic
Think of a FESTival of pests - an IN-FEST-ed place has an unwelcome festival of bugs or rats.
Conceptual Metaphor
NEGATIVE ENTITIES ARE INVADERS / A PLACE IS A HOST FOR PARASITES. Used to frame problems as active, living invaders taking over a space.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'infected' (зараженный вирусом/бактерией). 'Infested' is about larger pests/parasites (кише́чник, заражённый паразитами).
- The Russian 'кишащий' is a close equivalent for the 'teeming' sense.
Common Mistakes
- Using 'infected' for pest problems (e.g., 'The house was infected with mice' - incorrect).
- Using the active verb 'infest' incorrectly (e.g., 'Mice infested in the attic' should be 'Mice infested the attic' or 'The attic was infested with mice').
Practice
Quiz
Which sentence uses 'infested' correctly?
FAQ
Frequently Asked Questions
'Infested' refers to being overrun by visible pests or parasites (insects, rodents). 'Infected' refers to contamination by microorganisms like bacteria or viruses that cause disease.
Almost never. Its core meaning is negative. Using it positively is usually ironic or humorous (e.g., 'The garden was infested with butterflies' to mean 'full of').
Both are correct. 'Infested with' is more common, especially when describing the state. 'Infested by' is often used when emphasizing the agent of infestation.
The noun is 'infestation'. Example: 'The building had a severe rodent infestation.'
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