hairball: n. 1. [Fidonet] A large batch of messages that a store-and-forward
network is failing to forward when it should. Often used in the phrase
“Fido coughed up a hairball today”, meaning that the stuck
messages have just come unstuck, producing a flood of mail where there had
previously been drought.
2. An unmanageably huge mass of source code. “JWZ thought the
Mozilla effort bogged down because the code was a huge hairball.”
3. Any large amount of garbage coming out suddenly. “Sendmail
is coughing up a hairball, so expect some slowness accessing the
Internet.”