A facultative parasite refers to an organism that can live independently or as a parasite, depending on the availability of resources or conditions. Synonyms for this term include conditional parasite, opportunistic parasite, or parasitic opportunist. These terms suggest that the organism takes advantage of favorable conditions to become a parasite but can survive on its own when conditions are less favorable. Another synonym is a secondary parasite, which refers to an organism that becomes parasitic only after another organism has weakened the host. Overall, these synonyms highlight the flexible, adaptable nature of facultative parasites and their ability to exploit opportunities to their advantage.