noun, plural: commensalisms
A form of symbiosis between two organisms of different species in which one of them benefits from the association whereas the other is largely unaffected or not significantly harmed or benefiting from the relationship.
As a form of symbiosis, the organisms are typically found in close proximity despite of their differences in speciation. Although they thrive in the same area there is no major competition between them; rather, one of them benefits while the other is neither significantly harmed nor benefiting from the symbiosis. A common example is the symbiosis between the epiphyte orchids on branches of trees. These orchids benefit from the trees by the trees rendering support to the orchids. The orchids can gain more light and air in this way. The trees are neither drastically harmed nor benefiting from the orchids attached to their branches.
Word origin: Latin com- (together) + mensa (table)