pseudo-tty

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

pseudo-tty

   {Berkeley} {Unix} networking device which appears to an
   {application program} as an ordinary terminal but which is in
   fact connected via the network to a process running on a
   different {host} or a windowing system.  Pseudo-ttys have a
   slave half and a control half.  The slave tty (/dev/ttyp*) is
   the device that user programs use and the control tty
   (/dev/ptyp*) is used by {daemons} to talk to the net.

   (1994-11-08)