serial port

from WordNet (r) 3.0 (2006)

serial port
    n 1: an interface (commonly used for modems and mice and some
         printers) that transmits data a bit at a time

from The Free On-line Dictionary of Computing (8 July 2008)

serial port

   <hardware, communications> (Or "com port") A connector on a
   computer to which you can attach a {serial line} connected to
   peripherals which communicate using a serial (bit-stream)
   {protocol}.  The most common type of serial port is a 25-pin
   D-type connector carrying {EIA-232} signals.  Smaller
   connectors (e.g. 9-pin {D-type}) carrying a subset of EIA-232
   are often used on {personal computers}.  The serial port is
   usually connected to an {integrated circuit} called a {UART}
   which handles the conversion between serial and parallel data.

   In the days before bit-mapped displays, and today on
   {multi-user} systems, the serial port was used to connect one
   or more terminals ({teletypewriters} or {VDUs}), printers,
   {modems} and other serial peripherals.  Two computers
   connected together via their serial ports, possibly via
   {modems}, can communicate using a {protocol} such as {UUCP} or
   {CU} or {SLIP}.

   (1995-01-12)