five-plex
n.— «As with lofts and penthouses, the definition of a townhouse has expanded. Now the word is often used to mean any multilevel residence, no matter where you find it (the townhouse at Park South Lofts is a “five-plex” located not on the ground level but on the 16th floor of a prewar condo high-rise).» —“Townhouse Party” by Katherine Dykstra New York Post Oct. 26, 2006. (source: Double-Tongued Dictionary)