To preempt, manually or automatically, a prescribed procedure. Note: For example, one might manually override a prescribed course of action programmed to occur in the event of a fault. 2. In telephony, the entering of or seizure of, a busy circuit, i.e., an occupied circuit, by a party other than those using the circuit. Note: For example, an attendant might override a circuit after a busy verification, or a user with a higher precedence level might override a circuit.