WordNet (r) 3.0 (2006):

parallel port
    n 1: an interface between a computer and a printer where the
         computer sends multiple bits of information to the printer
         simultaneously [syn: parallel interface, parallel port]

The Free On-line Dictionary of Computing (30 December 2018):

parallel port

    An interface from a computer system where data is
   transferred in or out in parallel, that is, on more than one
   wire.  A parallel port carries one bit on each wire thus
   multiplying the transfer rate obtainable over a single wire.
   There will usually be some control signals on the port as well
   to say when data is ready to be sent or received.

   The commonest kind of parallel port is a printer port, e.g. a
   Centronics port which transfers eight bits at a time.  Disks
   are also connected via special parallel ports, e.g. SCSI or
   IDE.

   (1995-01-24)