alt
/awlt/ 1. n. The alt shift key on an IBM PC or clone
keyboard; see bucky bits, sense 2 (though typical PC usage does
not simply set the 0200 bit). 2. n. The `clover' or `Command'
key on a Macintosh; use of this term usually reveals that the
speaker hacked PCs before coming to the Mac (see also feature key).
Some Mac hackers, confusingly, reserve `alt' for the Option
key (and it is so labeled on some Mac II keyboards).
3. n.obs.
[PDP-10; often capitalized to ALT] Alternate name for the ASCII
ESC character (ASCII 0011011), after the keycap labeling on some
older terminals; also `altmode' (/awlt'mohd/). This character
was almost never pronounced `escape' on an ITS system, in
TECO, or under TOPS-10 --- always alt, as in "Type alt alt to
end a TECO command" or "alt-U onto the system" (for "log onto
the [ITS] system"). This usage probably arose because alt is more
convenient to say than `escape', especially when followed by
another alt or a character (or another alt and a character,
for that matter).