# symbiosis

/ˌsɪmbaɪˈoʊsəs/ (US) · /sˌɪmbaɪˈəʊsɪs/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/symbiosis
Updated: 2026-05-30

## Definition

a close relationship between two different living things where both benefit. It is like a partnership in nature where each side helps the other survive.

For teachers: a close and often long-term biological interaction between two different biological organisms, typically providing a benefit to both. In ecology, it describes a mutualistic relationship where both species derive a net benefit.

## Examples

- The relationship between bees and flowers is a perfect example of symbiosis.
- The study of coral reefs reveals a complex symbiosis between the polyps and the algae that live within their tissues, a partnership essential for the reef's survival in nutrient-poor waters.

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