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Last edited 03 Jul 2017
Historically, this would have been referred to as a maisonette, but the term duplex has become increasingly popular because of its perceived Americanism, and is generally applied to apartments with a more modern design, whereas a maisonette might be more traditional.
An apartment with three floors can be referred to as a triplex. There is some dispute about whether an apartment with a mezzanine level should be referred to as a duplex. Where a duplex is on the top floor of a high-rise building, it might also be referred to as a penthouse.
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