sym·​bi·​o·​sis | \ ˌsim-bē-ˈō-səs How to pronounce symbiosis (audio) , -ˌbī- \
plural symbioses\ ˌsim-​bē-​ˈō-​ˌsēz How to pronounce symbiosis (audio) \

Definition of symbiosis

1 : the living together in more or less intimate association or close union of two dissimilar organisms (as in parasitism or commensalism) especially : mutualism
2 : a cooperative relationship (as between two persons or groups) the symbiosis … between the resident population and the immigrants— John Geipel

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Did You Know?

Symbiosis was adopted by the scientific community in the late 1800s, though it had appeared in English in a non-scientific sense as far back as 1622. When a biological symbiosis is mutually beneficial, it is termed "mutualism." For example, when the yucca moth lays her eggs in the seed pods of the yucca, she acts as pollinator, and when the larvae hatch they feed on some, but not all, of the seeds. When one organism lives off another at the other’s expense, it’s called "parasitism." Either way, living together is what "symbiosis" is all about; the word came to us, via German and New Latin, from the Greek symbiōsis, meaning "state of living together." "Symbiōsis," in turn, traces to "symbios" ("living together"), a combination of syn-, meaning "with," and bios, meaning "life."

Examples of symbiosis in a Sentence

The bird lives in symbiosis with the hippopotamus. Their professional association was one of symbiosis.
Recent Examples on the Web New York roommate stories often begin with a kind of claustrophobic, reluctant symbiosis: Two people, linked solely by necessity, now also have to share the same bathroom. Bridget Read, Curbed, "The Nightmare Share," 2 Feb. 2021 Narcissistic symbiosis refers to the developmental wounds that make the leader-follower relationship magnetically attractive. Tanya Lewis, Scientific American, "The ‘Shared Psychosis’ of Donald Trump and His Loyalists," 11 Jan. 2021 There's a kind of narcissistic symbiosis that happens between him and his followers. Alison Medley, Chron, "How Trump ruined Americans' mental health," 7 Dec. 2020 Change can be frightening, even for those who disapprove of the symbiosis between church and state. New York Times, "In Poland, Protests Over Abortion Ban Could Revolutionize Politics," 7 Dec. 2020 That symbiosis makes a great deal of sense after so much time playing together with Tom. Gary Graff, cleveland, "‘Dirty Knobs’ frontman Mike Campbell relishes new role, and past with Tom Petty," 20 Nov. 2020 Robin Wall Kimmerer writes with gentleness and reassurance about the abundance that comes with reciprocity and symbiosis. Jennifer Day,, "Gift guide: Shopping for book lovers? Chicago booksellers have you covered.," 17 Nov. 2020 The symbiosis between Indianapolis and the NCAA extends beyond events. Zach Osterman, The Indianapolis Star, "The NCAA has been good to Indianapolis. Now, it needs Indy more than ever.," 16 Nov. 2020 That said, the symbiosis still exists, and that’s part of what makes a true revolution — a full dismantling of the court — seem improbable right now. Esther Mobley,, "The Court of Master Sommeliers’ sexual misconduct scandal could render it irrelevant," 12 Nov. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'symbiosis.' 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 symbiosis

1877, in the meaning defined at sense 1

History and Etymology for symbiosis

borrowed from German Symbiose, borrowed from Greek symbíōsis "living together, companionship," from symbiō-, variant stem of symbioûn "to live with, live together" (from sym- sym- + bioûn "to live, pass one's life," derivative of bíos "life") + -sis -sis — more at quick entry 1

Note: As a term in life sciences German Symbiose was promulgated, if not introduced, by the mycologist Heinrich Anton de Bary (1831-88) in Die Erscheinung der Symbiose: Vortrag gehalten auf der Versammlung der Deutscher Naturforscher und Aertze zu Cassel (Strassburg, 1879); a portion of the lecture appeared earlier as "Ueber Symbiose" in Der Naturforscher, 11. Jahrgang, No. 43, October 26, 1878, pp. 400-04. He defines the word briefly as "the living together of differently denominated organisms" ("[das] Zusammenleben ungleichnamiger Organismen," p. 5). De Bary was probably aware of the slightly earlier synonymous term Symbiotismus, introduced by the plant pathologist Albert Bernhard Frank (1839-1900) in "Ueber die biologischen Verhältnisse des Thallen einiger Krustenflechten," Beiträge zur Biologie der Pflanzen, Band 2 (1877), p. 195.

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The first known use of symbiosis was in 1877

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Last Updated

9 Feb 2021

Cite this Entry

“Symbiosis.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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More Definitions for symbiosis



English Language Learners Definition of symbiosis

biology : the relationship between two different kinds of living things that live together and depend on each other
formal : a relationship between two people or groups that work with and depend on each other


sym·​bi·​o·​sis | \ ˌsim-ˌbī-ˈō-səs How to pronounce symbiosis (audio) , -bē- How to pronounce symbiosis (audio) \
plural symbioses\ -​ˌsēz How to pronounce symbiosis (audio) \

Medical Definition of symbiosis

1 : the living together of two dissimilar organisms in more or less intimate association or close union
2 : the intimate living together of two dissimilar organisms in a mutually beneficial relationship especially : mutualism

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