A long-term symbiotic relationship refers to a situation where two or more organisms rely on each other for survival. In such relationships, each organism provides a service, such as food, shelter, or protection, to ensure the continued existence of the other. There are several synonyms for symbiotic relationships, including mutualism, commensalism, and parasitism. Mutualism refers to a relationship where both organisms benefit, while commensalism involves one organism benefiting without harming the other. On the other hand, parasitism refers to a relationship where one organism benefits at the expense of the other. Other terms used to describe long-term symbiotic relationships include interdependence, cooperation, and collaboration. These relationships are common in nature, and play a crucial role in the survival of many species.