- The amount of time a piece of equipment cannot be used due to failure, repair, or maintenance.
- The time during which a device, piece of equipment, or system is not operational. Causes include failures, routine maintenance, repairs, and power outages. Also spelled down time. Also called dead time (1), or off time (2).
- synonymdead time
- noun a period of time that a communications network is not functioning, because of breakdown or maintenance