parasitism

noun

par·​a·​sit·​ism ˈper-ə-sə-ˌti-zəm How to pronounce parasitism (audio)
-ˌsī-,
ˈpa-rə-
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
3

Examples of parasitism in a Sentence

Recent Examples on the Web Citizen scientists have made important discoveries and extended the range of zombie fly parasitism of honey bees to the Pacific Northwest, the eastern US, the eastern US, the southern US, and both western and eastern Canada. Guest, Discover Magazine, 9 Feb. 2017 Either way, the study adds to the scant overall knowledge of defenses against mimicry and brood parasitism. Sarah Kuta, Smithsonian Magazine, 28 July 2023 Barbe notes that basic natural processes like the nitrogen cycle don’t occur in the game, nor do key relationships between organisms, like parasitism. James Dinneen, Discover Magazine, 14 Apr. 2021 Many decades ago, researchers noticed that some ant species employ a more clandestine kind of parasitism. Viviane Callier, Quanta Magazine, 8 May 2023 But for them at least, brood parasitism is clearly not a simple case of grifters and marks. Ed Yong, Discover Magazine, 29 June 2011 In Frankopan’s telling, this is that same old story of parasitism writ large, now with planetary fallout. Ben Ehrenreich, The New Republic, 10 May 2023 Such a relationship between species is called obligate parasitism, because the parasites cannot survive on their own. Viviane Callier, Quanta Magazine, 8 May 2023 In each generation, prinias with unusual-looking eggs should be better able to avoid brood parasitism. Elizabeth Preston, Discover Magazine, 20 Apr. 2012

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'parasitism.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

circa 1611, in the meaning defined at sense 1

Time Traveler
The first known use of parasitism was circa 1611

Dictionary Entries Near parasitism

Cite this Entry

“Parasitism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/parasitism. Accessed 18 Apr. 2024.

Kids Definition

parasitism

noun
par·​a·​sit·​ism ˈpar-ə-sə-ˌtiz-əm How to pronounce parasitism (audio)
-ˌsīt-ˌiz-
: a close association between living things of two or more kinds of which one is a parasite obtaining benefits from the other which is a host and is usually harmed in some way

Medical Definition

parasitism

noun
par·​a·​sit·​ism ˈpar-ə-sə-ˌtiz-əm How to pronounce parasitism (audio) -ˌsīt-ˌiz- How to pronounce parasitism (audio)
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
2

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