noun
Computing term for a period during which a system is unresponsive or not processing input.
センサーの不動作時間を短くする必要がある。
We need to shorten the sensor's dead time.
Compound of 不 (fu, 'not') + 動作 (dōsa, 'operation') + 時間 (jikan, 'time'). The exact derivation is uncertain; it is a technical term likely coined in engineering contexts.