1. A frequent consequence of data arriving faster than it can be consumed, especially in serial line communications.For example, at 9600 baud there is almost exactly one character per millisecond, so if a silo can hold only two characters and the machine takes longer than 2 milliseconds to get to service the interrupt, at least one character will be lost.2. Also applied to non-serial-I/O communications."I forgot to pay my electric bill due to mail overrun.""Sorry, I got four phone calls in 3 minutes last night and lost your message to overrun."When thrashing at tasks, the next person to make a request might be told "Overrun!"Compare {firehose syndrome}.3. More loosely, may refer to a buffer overflow not necessarily related to processing time (as in {overrun screw}).[Jargon File]