The Vocalibrate dictionary

symbiosis

/ˌsɪmbiˈoʊsɪs/noun

a close relationship between two things that benefits both

Clownfish and sea anemones live in symbiosis, each protecting the other.

Near in meaning: interdependencepartnershipcooperationmutualism
In the family: symbiosessymbioticsymbioticallysymbiont

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