From WordNet (r) 2.0 :
command line interface
n : a user interface in which you type commands instead of
choosing them from a menu or selecting an icon [syn: CLI]
From The Free On-line Dictionary of Computing (27 SEP 03) :
command line interface
A means of communication between a
program and its user, based solely on textual input and
output. Commands are input with the help of a keyboard or
similar device and are interpreted and executed by the
program. Results are output as text or graphics to the
terminal.
Command line interfaces usually provide greater flexibility
than graphical user interfaces, at the cost of being harder
for the novice to use. Consequently, some hackers look down
on GUIs as designed For The Rest Of Them.
(1996-01-12)