infest

verb in·fest \ in-ˈfest \

Updated on: 17 May 2018

Definition of infest

transitive verb

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

—

infestant

play \in-ˈfe-stənt\ noun

—

infestation

play \ˌin-ˌfe-ˈstā-shən\ noun

—

infester

play \in-ˈfe-stər\ noun

See infest defined for English-language learners

See infest defined for kids

Examples of infest in a Sentence

in desperation, we called in an exterminator because the house was infested with ants

Recent Examples of infest from the Web

Ohio quarantine regulations restrict the movement of hemlock materials from areas known to be infested with the hemlock woolly adelgid into noninfested Ohio counties.

— sheila vilvens, Cincinnati.com, "The latest invasive insect has 'sucking mouthparts' that kill hemlock trees," 11 May 2018
Oak trees at more than 600 sites around London, many of which were infested with OPM for the last several years, will continue to be treated through June.

— julissa treviño, Smithsonian, "Londoners Beware: These Toxic Caterpillars Cause Rashes and Asthma," 1 May 2018
Nic Cage’s ex claims her rental house is infested with toxic black mold that makes her sick.

— mark shanahan, BostonGlobe.com, "Former ambassador Rufus Gifford adds celebrity sizzle to congressional race," 24 Apr. 2018
Watson left an apartment in Port Richmond that was infested with rats.

— julia terruso, Philly.com, "Why 1 in 14 Philly renters faces eviction every year," 18 Apr. 2018
Soooo many Sanctuary areas want OUT of this ridiculous, crime infested & breeding concept.

— john wildermuth, San Francisco Chronicle, "Jerry Brown sends National Guard to the border, but on his terms, not Trump’s," 18 Apr. 2018
Trump’s first great project in the Big Apple was rebuilding a hotel at Grand Central Station in the 1970s, when New York City was crime-infested and broke, its leaders desperate.

— nina burleigh, Newsweek, "Trump vs. Mueller: Is the American Legal System Any Match for the President?," 8 Mar. 2018
The Chijuk sale is 60 percent birch and 40 percent spruce that's infested with beetles, Oien said.

— zaz hollander, Anchorage Daily News, "Mat-Su floats major new timber venture. But is it too good to be true?," 8 Apr. 2018
The quarantine is aimed at limiting the scale's spread in wetlands as well as agricultural areas, where it is feared the insect may infest sugar cane, sorghum and rice crops.

— tristan baurick, NOLA.com, "Congress pours money into fight against Louisiana's wetland pest," 29 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infest.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of infest

French infester, from Latin infestare, from infestus hostile

NEW! Time Traveler

First Known Use: 1602

in the meaning defined at sense 1

See Words from the same year

infest Synonyms

Synonyms

overrun;

Related Words

beset, overspread, overwhelm;

abound, crawl, teem;

annoy, pester, plague;

contaminate, infect;

INFEST Defined for English Language Learners

infest

verb

Definition of infest for English Language Learners

of something harmful or unwanted : to be in or over (a place, an animal, etc.) in large numbers

INFEST Defined for Kids

infest

verb in·fest \ in-ˈfest \

Definition of infest for Students

infested; infesting

: to spread or swarm in or over in a harmful manner Termites infested the tree.

Medical Dictionary

infest

transitive verb in·fest \ in-ˈfest \

medical Definition of infest

: to live in or on as a parasite

the flea that infests cats

horses infested with worms

— compare infect

Learn More about infest

Thesaurus: All synonyms and antonyms for infest Spanish Central: Translation of infest Nglish: Translation of infest for Spanish speakers Britannica English: Translation of infest for Arabic speakers

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infest

Definition of infest

infestant

infestation

infester

Examples of infest in a Sentence

Recent Examples of infest from the Web

Origin and Etymology of infest

infest Synonyms

Synonyms

Related Words

INFEST Defined for English Language Learners

infest

Definition of infest for English Language Learners

INFEST Defined for Kids

infest

Definition of infest for Students

Medical Dictionary

infest

medical Definition of infest

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