1. adj. Not operating. "The up escalator is down"
is considered a humorous thing to say (unless of course you were
expecting to use it), and "The elevator is down" always means
"The elevator isn't working" and never refers to what floor the
elevator is on. With respect to computers, this term has passed
into the mainstream; the extension to other kinds of machine is
still confined to techies (e.g. boiler mechanics may speak of a
boiler being down). 2. `go down' vi. To stop functioning;
usually said of the system. The message from the console
that every hacker hates to hear from the operator is "System going
down in 5 minutes". 3. `take down', `bring down' vt. To
deactivate purposely, usually for repair work or PM. "I'm
taking the system down to work on that bug in the tape drive."
Occasionally one hears the word `down' by itself used as a verb
in this vt. sense. See crash; oppose up.