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duplex

A two-family house can be called a duplex. Living in a duplex is great — unless the people with whom you share a wall like to have all-night yodeling parties.

In the U.K. a duplex is an apartment with an upstairs and a downstairs, but in North America a duplex is a building divided into two separate living spaces. Most duplexes are built with the two homes side by side, although you can also live in a duplex with apartments on two floors. The Latin duplex means "twofold," from duo, "two," and -plex, "to intertwine." The word was coined in the U.S. around 1922.

Definitions of duplex
  1. noun
    a house with two units sharing a common wall
    synonyms: duplex house, semidetached house
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    type of:
    house
    a dwelling that serves as living quarters for one or more families
  2. noun
    an apartment having rooms on two floors that are connected by a staircase
    synonyms: duplex apartment
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    type of:
    apartment, flat
    a suite of rooms usually on one floor of an apartment house
  3. adjective
    (used technically of a device or process) having two parts
    “a duplex transaction”
    Synonyms:
    multiple
    having or involving or consisting of more than one part or entity or individual
  4. adjective
    allowing communication in opposite directions simultaneously
    duplex system”
    duplex telephony”
    Synonyms:
    bidirectional
    reactive or functioning or allowing movement in two usually opposite directions
  5. verb
    change into a duplex
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    type of:
    convert
    change the nature, purpose, or function of something
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