IPA: /ˈdaʊnˌtaɪm/
KK: /ˈdaʊnˌtaɪm/
A period when something is not working or is not in use, often due to repairs or maintenance.
The factory experienced a lot of downtime last month due to equipment failures.
Downtime is formed from "down" (from Old English "dūne", meaning down or lower) and "time" (from Old English "tīma", meaning a period or duration). The word refers to a period of time when something is not operational or functioning, often used in the context of machines or systems being inactive.
Think of a time when things are 'lower' or not working ('down') — that's what 'downtime' means, a period when something is not in operation.