adjective quad·ru·plex \ˈkwädrəˌpleks\

Definition of quadruplex

  1. :  being or relating to a system of telegraphy by which two messages in each direction may be sent simultaneously over one wire

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Origin and Etymology of quadruplex

Latin quadruplic-, quadruplex fourfold, from quadri- + -plic-, -plex -fold — more at simple

Seen and Heard

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a trip made at another's expense

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