Abend

[Greta]

Short for Abnormal end. An abend is an unexpected or abnormal end to a process. In computer software, it typically refers to a software crash when a program unexpectedly quits. For example, an error in a programs code may cause it to freeze or crash while running a certain command. The result is an unexpected (and often inconvenient) end to the program.
The term ABEND was initially used by IBM OS/360 systems as an error message. It is now used by Novell Netware systems and also as a general programming term.

[Jessica]

ABnormal END - Abnormal termination (of software); {crash}; {[lossage]}. Derives from an [error message] on the IBM 360; used jokingly by hackers but seriously mainly by {code grinder}s. Usually capitalized, but may appear as abend because it is what system operators do to the machine late on Friday when they want to [call it a day], and hence is from the German Evening.

[Julian]

[Absent] By Enforced Net Deprivation. Used to explain to fellow netizens (especially on [USENET]) that one will be losing (or has not had) Internet access for some time [for reasons] outside ones control.