What does infest mean?
Infest is a verb meaning to occupy a place in large numbers, usually in a way that is unwelcome. Its most familiar use describes insects, parasites, weeds, or other organisms taking over a building, garden, animal, or natural habitat: a kitchen may be infested with ants, while a field may become infested with weeds. The word can also apply figuratively to persistent troubles or worries that trouble a person, organization, or place. In these uses, infest suggests both abundance and an undesirable quality: the organisms or problems are not merely present but are difficult to control or tolerate. Although related to infect, infest emphasizes swarming or large-scale occupation rather than the transmission of disease. The word derives from Latin infestare, “to occupy as an enemy,” which reflects its longstanding association with an unwelcome force taking possession of something.
To occupy or affect a place in large numbers, especially with insects, parasites, weeds, or other unwelcome organisms; to swarm.
"The abandoned building was infested with termites."
Often used with “with”: infested with fleas, lice, insects, or weeds.
To trouble or plague a person, place, or organization persistently with difficulties.
"The new manager was infested with problems inherited from the previous administration."
From Latin infestare, meaning “to occupy as an enemy,” infest still carries the sense of an unwelcome force taking over a place.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does infest come from?
The English verb comes from Latin infestare, meaning “to occupy as an enemy” or “to attack.” Latin infestare was derived from infestus, “hostile,” “dangerous,” or “occupied by an enemy.” English later developed the verb in the sense of being overrun by pests and, more figuratively, of being persistently troubled.
Related word forms
How infest is actually used
The word commonly has an unpleasant or threatening connotation. It is especially frequent in descriptions of vermin, parasites, weeds, and other unwelcome organisms, and is also used figuratively for persistent difficulties.
Easily confused with infest
Infest usually means to swarm or occupy in large numbers, whereas infect means to transmit disease or contamination to an organism.