bio-, bi-, -bia, -bial, -bian, -bion, -biont, -bius, -biosis, -bium, -biotic, -biotical
(Greek: life; living, live, alive)
Don’t confuse this element with another bi- which means "two".
The most important things in life are not things.
The term tends to be used more in reference to mutualists (relation between two different species of organisms that are interdependent; each gains benefits from the other) than to parasites, commensals (relationship in which one species derives some benefit while the other is unaffected), or other types of symbionts.
2. Association of two different organisms (usually two plants, or an animal and a plant) which live attached to each other, or one as a tenant of the other, and contribute to each other’s support.
Also more widely, any intimate association of two or more different organisms, whether mutually beneficial or not.3. The biological association of two or more species for their mutual benefit.
4. The mutual cooperation or interdependence of two people, as mother and infant, or husband and wife; sometimes used to denote excessive or pathological interdependence of two persons.
Here is more information and several illustrations about symbiosis.
2. A reference to an organism obtaining nourishment through a symbiotic relationship.