n. The high half of a 512K PDP-10's
physical address space; the other half was of course the low moby. This
usage has been generalized in a way that has outlasted the
PDP-10; for example, at the 1990 Washington D.C. Area Science
Fiction Conclave (Disclave), when a miscommunication resulted in two
separate wakes being held in commemoration of the shutdown of MIT's
last ITS machines, the one on the upper floor was dubbed the
'high moby' and the other the 'low moby'. All parties involved
grokked this instantly.
See moby.