Definition of "brownout"

A period of low alternating current line voltage, causing a reduction in illumination.  examples

Temporary dimming of vision, usually with a brown hue and accompanied by loss of peripheral vision or tunnel vision.  examples

Temporary closing of a fire station, usually due to budget restrictions.  examples

A power outage during the day; distinguished from a blackout, which occurs at night  examples

(Philippines, some other countries) A blackout, regardless of time of day.  quotations  examples