a period of time when there is no electricity supply 停电，断电SYN power failure, British English power cut
Examples from the Corpus
power outage• Play was delayed for two hours by a power outage.• She could not breathe on her own enough to survive a power outage longer than a breath or two.• The midday power outage also caused traffic snarls as police officers directed traffic through intersections whose signals had gone dark.• He said there was no power outage.• From retail stores to hospitals to universities, doors remained open as back-up generators kicked in almost immediately following the power outage.