mu·​tu·​al·​ism ˈmyü-chə-wə-ˌli-zəm How to pronounce mutualism (audio)
: the doctrine or practice of mutual dependence as the condition of individual and social welfare
: mutually beneficial association between different kinds of organisms
ˈmyü-chə-wə-list How to pronounce mutualism (audio)
ˌmyü-chə-wə-ˈli-stik How to pronounce mutualism (audio)

Example Sentences

Recent Examples on the Web Partnerships between ants and trees are classic examples of mutualism in nature---the trees provide room and board for the ant colonies who protect the trees from pests. Breanna Draxler, Discover Magazine, 7 Nov. 2013 This metabolic mutualism helps trees to survive in all kinds of different environmental conditions and expand their ecological niche. Quanta Magazine, 19 Dec. 2022 Power and temptation cause shifts between exploitation and cooperation in a cleaner wrasse mutualism, Proc. Christie Wilcox, Discover Magazine, 24 Apr. 2013 Other living things have evolved to snatch up the rewards of mutualism with none of the costs. Kristin Ohlson, Discover Magazine, 2 Jan. 2019 But there’s also metabolic mutualism — the acquisition of metabolism through this really intimate partnership between two organisms. Quanta Magazine, 19 Dec. 2022 Anyone who has hiked in a forest may have noted lichens formed from a union of fungi and algae, without realizing that these are prime examples of mutualism. Jerome Groopman, The New Yorker, 5 Dec. 2022 And both fig and fig wasp are utterly reliant on one another to survive—a phenomenon called mutualism. Ali Francis, Bon Appétit, 7 Sep. 2022 That’s an example of mutualism, a term for whenever one animal helps another. Erika Larsen, National Geographic, 1 Oct. 2020 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mutualism.' 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

1845, in the meaning defined at sense 1

Time Traveler
The first known use of mutualism was in 1845

Dictionary Entries Near mutualism

Cite this Entry

“Mutualism.” Dictionary, Merriam-Webster, Accessed 2 Jun. 2023.

Kids Definition


mu·​tu·​al·​ism ˈmyüch-(ə-)wə-ˌliz-əm How to pronounce mutualism (audio)
: association between different kinds of organisms that benefits both

Medical Definition


: mutually beneficial association between different kinds of organisms
mutualist noun

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