par·​a·​sit·​ism | \ ˈper-ə-sə-ˌti-zəm How to pronounce parasitism (audio) , -ˌsī-, ˈpa-rə- \

Definition of parasitism

1 : the behavior of a parasite
2 : an intimate association between organisms of two or more kinds especially : one in which a parasite obtains benefits from a host which it usually injures

Examples of parasitism in a Sentence

Recent Examples on the Web Although there are few long-term data sets on any parasite species, there are one-off studies that document the abundance of parasitism at a particular place and time. Rachel Nuwer, Scientific American, 28 Apr. 2022 The only way to test this hypothesis would be to compare present parasitism rates with those from the past. Rachel Nuwer, Scientific American, 28 Apr. 2022 Biologists have observed, over long periods of time, that species that are obligate parthenogens frequently die out from disease, parasitism or changes in habitat. Mercedes Burns, CNN, 27 Dec. 2021 That’s because dozens of bird species are thought to engage in some form of brood parasitism, each with their own violent flair. Katherine J. Wu, The Atlantic, 26 Oct. 2021 This practice is called brood parasitism and is unique on our continent to cowbirds. Val Cunningham Special To The Star Tribune, Star Tribune, 6 July 2021 One of the boldest themes is the concept of parasitism, something many insitutions have been accused of in what some see is their haste to receive credits for superficial attempts at being anti-racist. Keyaira Boone, Essence, 25 June 2021 Foitzik told me that her team couldn’t find any overt downsides to life as an infected ant, a finding that appears to shatter the standard paradigm of parasitism. Katherine J. Wu, The Atlantic, 18 May 2021 Yet despite their parasitism, mistletoes may well be the Robin Hoods of plants. Rachel Ehrenberg, Smithsonian Magazine, 23 Dec. 2020 See More

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

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First Known Use of parasitism

circa 1611, in the meaning defined at sense 1

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The first known use of parasitism was circa 1611

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Last Updated

17 May 2022

Cite this Entry

“Parasitism.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for parasitism


par·​a·​sit·​ism | \ ˈpar-ə-sə-ˌtiz-əm How to pronounce parasitism (audio) , -ˌsīt-ˌiz- How to pronounce parasitism (audio) \

Medical Definition of parasitism

1 : an intimate association between organisms of two or more kinds especially : one in which a parasite obtains benefits from a host which it usually injures

More from Merriam-Webster on parasitism Encyclopedia article about parasitism


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