infested; infesting; infests
1
: to spread or swarm in or over in a troublesome manner
a slum infested with crime
shark-infested waters
2
: to live in or on as a parasite
Examples of infest in a Sentence
in desperation, we called in an exterminator because the house was infested with ants
Recent Examples on the Web
Discard anything that is damaged or obviously infested, tying it in a plastic bag and throwing it away.
—
Brandee Gruener, Southern Living, 31 Oct. 2025
The whole property was infested with rats.
—Colson Thayer, PEOPLE, 31 Oct. 2025
Of the more than five thousand tributaries that empty into the Great Lakes, about one in ten is infested with lampreys.
—Katie Thornton, New Yorker, 24 Oct. 2025
Money trees infested with pests or diseases may develop brown leaves.
—Leanne Potts, Better Homes & Gardens, 21 Oct. 2025
See All Example Sentences for infest
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Brandee Gruener, Southern Living, 31 Oct. 2025
The whole property was infested with rats.
—Colson Thayer, PEOPLE, 31 Oct. 2025
Of the more than five thousand tributaries that empty into the Great Lakes, about one in ten is infested with lampreys.
—Katie Thornton, New Yorker, 24 Oct. 2025
Money trees infested with pests or diseases may develop brown leaves.
—Leanne Potts, Better Homes & Gardens, 21 Oct. 2025
See All Example Sentences for infest
Cite this Entry
“Infest.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infest. Accessed 4 Nov. 2025.
Copy CitationKids Definition
infest
verb
in·fest
in-ˈfest 
1
: to spread or swarm in or over in a troublesome manner
a neighborhood infested with crime
shark-infested waters
2
: to live in or on as a parasite
horses infested with worms
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