The time of dawn.
The amount of time lost due to forces beyond one's control, as with a computer crash.
(figuratively) The time when something is just beginning. en
A period of time set aside for rest and relaxation; leisure time.
‘I've been working all weekend. I need some downtime.’;
a period of time when something (as a machine or factory) is not operating (especially as a result of malfunctions)
The term downtime is used to refer to periods when a system is unavailable. The unavailability is the proportion of a time-span that a system is unavailable or offline.