Symbiosis

English Meaning

The living together in more or less imitative association or even close union of two dissimilar organisms. In a broad sense the term includes parasitism, or antagonistic, or antipathetic, symbiosis, in which the association is disadvantageous or destructive to one of the organisms, but ordinarily it is used of cases where the association is advantageous, or often necessary, to one or both, and not harmful to either. When there is bodily union (in extreme cases so close that the two form practically a single body, as in the union of algæ and fungi to form lichens, and in the inclusion of algæ in radiolarians) it is called conjunctive symbiosis; if there is no actual union of the organisms (as in the association of ants with myrmecophytes), disjunctive symbiosis.

1. Biology A close, prolonged association between two or more different organisms of different species that may, but does not necessarily, benefit each member.
2. A relationship of mutual benefit or dependence.