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symbiosis

American  
[sim-bee-oh-sis, -bahy-] / ˌsɪm biˈoʊ sɪs, -baɪ- /

noun

  • symbioses
    plural
  1. Biology.

    1. the living together of two dissimilar organisms, as in mutualism, commensalism, amensalism, or parasitism.

    2. (formerly) mutualism.

  2. Psychiatry. a relationship between two people in which each person is dependent upon and receives reinforcement, whether beneficial or detrimental, from the other.

  3. Psychoanalysis. the relationship between an infant and their mother in which the infant is dependent on the mother both physically and emotionally.

  4. any interdependent or mutually beneficial relationship between two persons, groups, etc.


symbiosis British  
/ ˌsɪmbɪˈəʊsɪs, ˌsɪmbaɪˈəʊsɪs /

noun

  1. a close and usually obligatory association of two organisms of different species that live together, often to their mutual benefit

  2. a similar relationship between interdependent persons or groups

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

symbiosis Scientific  
/ sĭm′bē-ōsĭs /
  1. The close association between two or more organisms of different species, often but not necessarily benefiting each member. The association of algae and fungi in lichens and of bacteria living in the intestines or on the skin of animals are forms of symbiosis. Some scientists believe that many multicellular organisms evolved from symbiotic relationships between unicellular ones and that the DNA-containing organelles within certain eukaryotic cells (such as mitochondria and chloroplasts) are the product of symbiotic relationships in which the participants became interdependent. There are four forms of symbiosis: amensalism, commensalism, mutualism, and parasitism.


symbiosis Cultural  
  1. The process by which two organisms live together, usually to their mutual benefit. An example of a symbiotic pair are cows and the bacteria that live in their digestive tracts, enabling them to digest cellulose in grass.


Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of symbiosis

First recorded in 1615–25; from Greek symbíōsis, equivalent to sym- sym- + biō (variant stem of bioûn “to live”) + -sis -sis

Explanation

Symbiosis, a noun, tells about the relationship between living things that helps all of them stay alive, like the symbiosis between bees that eat nectar from flowers that get cross-pollinated when the bees move from one to the next. To correctly pronounce symbiosis, accent the third syllable: "sim-be-OH-sis." The prefix syn comes from the Greek word "together" and bios means "life." So symbiosis means "a living together." Things that live in symbiosis depend on one another, like the clown fish and anemone that protect one another from ocean predators, or the symbiosis between a dairy farmer and one who grows hay, trading milk for hay bales that feed the cows.

Keep Reading on Vocabulary.com

Vocabulary lists containing symbiosis

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Located at the bottom of the world, it’s hard to imagine a place more closely connected to nature, where New Zealand’s Māori communities have long lived in symbiosis with the land.

From Salon Jul. 26, 2026

"Most life on Earth is microbial, driving nutrient cycles and ecosystem function while revealing new dimensions of biological diversity through symbiosis," said Grosell.

From Science Daily May 31, 2026

"I think there's a really nice symbiosis between the two of them, but honestly a lot of it is work, it's connecting off the pitch, it's preparation and it's understanding what they see."

From BBC May 23, 2026

Investors are betting that objective symbiosis and Mexican President Claudia Sheinbaum’s skilled Trump whispering will renew the pact with minimal changes.

From Barron's Feb. 12, 2026

The nitrogen-fixing rhizobia in root nodules, the mycetomes of insects, and the enzyme-producing colonies in the digestive tracts of many animals are variations of this meticulously symmetrical symbiosis.

From "The Lives of a Cell" by Lewis Thomas

"These areas likely harbor similar microbial symbioses, which means that these interactions impact ecosystem functioning on a global scale."

From Science Daily May 15, 2024

It's impossible take a walk in the woods, eat a meal, or dip in the ocean, without participating in the deep symbioses that have nourished life's plenitude.

From Salon May 30, 2021

And fungi are major players in some of the most blockbuster symbioses in the history of the planet.

From Scientific American Jun. 24, 2020

It is one of the oldest and most successful symbioses in nature, said Toby Spribille, a lichen expert at the University of Graz in Austria, and the lead author of the new paper.

From New York Times Jul. 21, 2016

Animals in this phylum show parasitic and commensal symbioses with other species in their habitat.

From Textbooks Jan. 1, 2015

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