ANGLE BRACKETS (primarily MIT)
n. Either of the characters "<" and ">". See BROKET.

AOS (aus (East coast) ay-ahs (West coast)) [based on a PDP-10 increment instruction]
v. To increase the amount of something. "Aos the campfire." Usage: considered silly. See SOS.

ARG
n. Abbreviation for "argument" (to a function), used so often as to have become a new word.

AUTOMAGICALLY
adv. Automatically, but in a way which, for some reason (typically because it is too complicated, or too ugly, or perhaps even too trivial), I don't feel like explaining to you. See MAGIC. Example: Some programs which produce XGP output files spool them automagically.