[myoo-choo-uh-liz-uh
m] 
| 1. | a relationship between two species of organisms in which both benefit from the association. |
| 2. | the doctrine that the interdependence of social elements is the primary determinant of individual and social relations, esp. the theory that common ownership of property, or collective effort and control governed by sentiments of brotherhood and mutual aid, will be beneficial to both the individual and society. |
| 3. | Sociology. the force or principle of mutual aid. |
| mu·tu·al·ism (myōō'chōō-ə-lĭz'əm) n. An association between organisms of two different species in which each member benefits. mu'tu·al·is'tic adj. |
mutualism mu·tu·al·ism (my&oomacr;'ch&oomacr;-ə-lĭz'əm)
n.
A symbiotic relationship in which both species benefit.
mutualism
association between organisms of two different species in which each is benefited. Mutualistic arrangements are most likely to develop between organisms with widely differing living requirements. The partnership between nitrogen-fixing bacteria and leguminous plants is an example, as is the association between cows and rumen bacteria (the bacteria live in the digestive tract and help digest the plants eaten by the cow). The associations between tree roots and certain fungi are often mutualistic (see mycorrhiza.)
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