Antonyms of noun uptime

1 sense of uptime

Sense 1
uptime -- (a period of time when something (as a machine or factory) is functioning and available for use)
       Antonym of downtime (Sense 1)
      => downtime -- (a period of time when something (as a machine or factory) is not operating (especially as a result of malfunctions))

Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun uptime

1 sense of uptime

Sense 1
uptime -- (a period of time when something (as a machine or factory) is functioning and available for use)
       => time period, period of time, period -- (an amount of time; "a time period of 30 years"; "hastened the period of time of his recovery"; "Picasso's blue period")