n : a period of time when something (as a machine or factory) is not operating (especially as a result of malfunctions)
[jargon] A period of time during which a (computer) system is not operational, due to a malfunction or maintenance
Tip of the Iceberg will be experiencing downtime (or down-time; take your pick) this weekend. It has been determined that the Terri B. module is not operating properly as a result of malfunctions and will be undergoing maintenance. For an explanation, please see How to Turn Lemons into Lemonade.
We hope to have Terri B. back and functioning at capacity by Monday.