Duplex

How to spell duplex

6 letters · 2 syllables

How to pronounce duplex

Say the part in capitals loudest.

What does duplex mean?

1. nounA residential building divided into two separate homes, or an apartment spread over two floors.
2. adjectiveHaving two parts or working in two directions at once; double.

Duplex in a sentence

• noun

  They rented the upper half of a duplex near the station.

• adjective

  The office printer can run in duplex mode to print on both sides.

• noun

  The couple bought a duplex and live in one unit while letting the other.

• adjective

  The system uses a duplex connection so data flows in both directions simultaneously.

Where does duplex come from?

Language of origin: Latin

This word comes straight from the Latin duplex, meaning 'twofold' or 'double', which was assembled from duo, the Latin word for 'two', and the element -plex, related to the verb plicare, meaning 'to fold'. So at its root a duplex is literally something folded into two parts, the same image that gives us 'pliable' and 'complicated'. English adopted the term in the 1800s, first in technical and scientific senses describing things that worked in pairs or doubles, and it appears in 'duplex telegraphy', where signals travelled in two directions at once. In the housing sense it spread strongly in North American usage to mean a building split into two separate homes, while the British more often say it of a flat occupying two floors. The clean Latin spelling explains why duplex keeps its tidy -plex ending rather than anything resembling the everyday word 'double'.

How the word is built

• du- (from duo: two)
• -plex (fold, from Latin plicare: to fold)