Sputnik virophage is a specific term that refers to a subset of virophages, which are small viruses that parasitize other viruses. As such, there are no direct synonyms for the term. However, there are related terms that could be used to describe or discuss virophages more broadly. For example, a virophage could be described as a viral parasite, or as a type of virus that infects other viruses. Additionally, terms like "viral satellite" or "helper virus" may be used in some contexts to refer to similar phenomena. Overall, while there may not be direct synonyms for sputnik virophage, there are plenty of related terms that could be used to describe similar concepts in virology.