"Eightplex" is a term used to describe a building or complex with eight units, typically used in the real estate industry. It is an uncommon term and has few synonyms, with "octaplex" being the closest alternative. Other terms that may be used to describe an eight-unit building or complex include "eight-unit apartment complex," "eight-unit dwelling," or simply "eight apartments." However, these terms do not provide the same level of specificity as "eightplex." It is worth noting that different industries may use different terminology, and the number eight may be referred to using different prefixes depending on the context.