par·​a·​sit·​ize ˈper-ə-sə-ˌtiz How to pronounce parasitize (audio)
parasitized; parasitizing

transitive verb

: to infest or live on or with as a parasite
ˌper-ə-sə-tə-ˈzā-shən How to pronounce parasitize (audio)

Example Sentences

Recent Examples on the Web If they're drawn, the wasps that parasitize them should be drawn, too. Christie Wilcox, Discover Magazine, 27 Nov. 2012 Fungi can also parasitize and kill insects, including those troublesome to us. Kenneth Miller, Discover Magazine, 30 May 2013 As science journalist Rachel Nuwer writes, as many as 40 to 50 percent of all animal species are parasites, and almost every other species has at least one parasite that has evolved to parasitize it. Laura Helmuth, Scientific American, 1 May 2022 But humans moved in and cut forests, essentially creating more plains, allowing cowbirds to move into more areas to parasitize more species. Val Cunningham Special To The Star Tribune, Star Tribune, 6 July 2021 These almost microscopic wasps emerge from the sandpaper-looking material and fly off to parasitize and destroy pest moth eggs. Howard Garrett, Dallas News, 8 Mar. 2021 Follow-up studies have shown the wasps can find beetles, parasitize them, and reproduce; in some trees, up to 80% of ash borer larvae have wasps living inside them. Gabriel Popkin, Science | AAAS, 12 Nov. 2020 All of the 50 or so species in the genus have larvae that are dependent on birds for their nutrition; to date they are known to parasitize over 150 birds, from hawks to hummingbirds. Popular Science, 20 Oct. 2020 The latest organisms that researchers have looked to are bacteria in the microbiomes of roundworms that parasitize insects (technically termed enteropathogenic nematodes). Diana Gitig, Ars Technica, 20 Nov. 2019 See More

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

Word History

First Known Use

1872, in the meaning defined above

Time Traveler
The first known use of parasitize was in 1872

Dictionary Entries Near parasitize

Cite this Entry

“Parasitize.” Dictionary, Merriam-Webster, Accessed 23 Mar. 2023.

Kids Definition


par·​a·​sit·​ize ˈpar-ə-sə-ˌtīz How to pronounce parasitize (audio)
parasitized; parasitizing
: to infest or live on or with as a parasite
an insect that parasitizes many mammals

Medical Definition


transitive verb
variants also British parasitise
parasitized also British parasitised; parasitizing also British parasitising
: to infest or live on or with as a parasite
parasitization noun
also British parasitisation
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