The Jargon File (version 4.4.7, 29 Dec 2003):

smart terminal
 n.

    1. A terminal that has enough computing capability to render graphics or to
    offload some kind of front-end processing from the computer it talks to.
    The development of workstations and personal computers has made this term
    and the product it describes semi-obsolescent, but one may still hear
    variants of the phrase act like a smart terminal used to describe the
    behavior of workstations or PCs with respect to programs that execute
    almost entirely out of a remote server's storage, using local devices as
    displays.

    2. obs. Any terminal with an addressable cursor; the opposite of a glass
    tty. Today, a terminal with merely an addressable cursor, but with none of
    the more-powerful features mentioned in sense 1, is called a dumb terminal
    .

    There is a classic quote from Rob Pike (inventor of the blit terminal): ?
    A smart terminal is not a smartass terminal, but rather a terminal you can
    educate.? This illustrates a common design problem: The attempt to make
    peripherals (or anything else) intelligent sometimes results in finicky,
    rigid ?special features? that become just so much dead weight if you try to
    use the device in any way the designer didn't anticipate. Flexibility and
    programmability, on the other hand, are really smart. Compare hook.


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

intelligent terminal
smart terminal

    (or "smart terminal", "programmable terminal") A
   terminal that often contains not only a keyboard and screen,
   but also comes with a disk drive and printer, so it can
   perform limited processing tasks when not communicating
   directly with the central computer.  Some can be programmed by
   the user to perform many basic tasks, including both
   arithmetic and logic operations.  In some cases, when the user
   enters data, the data will be checked for errors and some
   type of report will be produced.  In addition, the valid data
   that is entered may be stored on the disk, it will be
   transmitted over communication lines to the central computer.

   An intelligent terminal may have enough computing capability
   to draw graphics or to offload some kind of front-end
   processing from the computer it talks to.

   The development of workstations and personal computers has
   made this term and the product it describes semi-obsolescent,
   but one may still hear variants of the phrase "act like a
   smart terminal" used to describe the behaviour of workstations
   or PCs with respect to programs that execute almost entirely
   out of a remote server's storage, using said devices as
   displays.

   The term once meant any terminal with an addressable cursor;
   the opposite of a glass tty.  Today, a terminal with merely
   an addressable cursor, but with none of the more-powerful
   features mentioned above, is called a dumb terminal.

   There is a classic quote from Rob Pike (inventor of the blit
   terminal): "A smart terminal is not a smart*ass* terminal, but
   rather a terminal you can educate".  This illustrates a common
   design problem: The attempt to make peripherals (or anything
   else) intelligent sometimes results in finicky, rigid "special
   features" that become just so much dead weight if you try to
   use the device in any way the designer didn't anticipate.
   Flexibility and programmability, on the other hand, are
   *really* smart.

   Compare hook.

   (1995-04-14)