- (of a flat)
with rooms on two floors （占两层楼的）复式住宅；跃层公寓 a duplex apartment 复式公寓 The duplex penthouses cover the top two floors of the building. 复式顶层公寓覆盖建筑物的顶层两层。
- (North American English)
(of a house 房子 joined to another house by a wall on one side that is shared 半独立式的 a duplex house/villa 双层别墅
- (of a printer or its software)
able to print on both sides of the paper This model comes with nice features such as Wi-Fi and duplex printing. 该型号具有不错的功能，例如Wi-Fi和双面打印。
- (of communications systems, computer systems, radio, etc.)
allowing signals to be sent in both directions at the same time A common application of duplex communication is in online chat systems. 双工通信的常见应用是在线聊天系统中。
- (North American English)
a building divided into two homes or apartments with separate entrances 二联式住宅；双拼房屋 
- (British English)
a flat with rooms on two floors （占两层楼的）复式住宅；跃层公寓 - (Australian English, North American English)
a house that is joined to another house by a wall on one side that is shared; a semi-detached house
Word Originmid 16th cent. (as an adjective): from Latin duplex, duplic-, from duo ‘two’ + plicare ‘to fold’. The noun dates from the 1920s.