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:
    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”
    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”
    reactive or functioning or allowing movement in two usually opposite directions
  5. verb
    change into a duplex
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    type of:
    change the nature, purpose, or function of something
Word Family

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