what is duplex? Share with your friends Share 0 Shivangi Singh answered this Duplex means double storeyed. . like u have duplex apartments... kindly ask in which context u want to know the meaning. .. hope it helps!!! :) 3 View Full Answer Deepak Agarwal answered this duplex house is a dwelling having apartments with separate entrances for two households. This includes two-story houses having a complete apartment on each floor and also side-by-side apartments on a single lot that share a common wall. 0