brownout

noun

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

   “When demand for electricity exceeds the available supply, a brownout occurs.”

2. A temporary dimming of vision, usually with a brown hue and accompanied by loss of peripheral vision or tunnel vision.

   “On rising suddenly from her chair she experienced a brownout and had to sit down again quickly.”

3. A temporary closing of a fire station, usually due to budget restrictions.

   “Fire departments across the country have been forced to rely on rolling brownouts because of the recession.”

4. A power outage during the day; distinguished from a blackout, which occurs at night.
5. (figuratively, uncommon)A moment or period where something is weakened, diminished or less effective.
6. (Australia, Hong-Kong, Philippines)A blackout, regardless of time of day.

   “Remember that you can't send or receive a fax if there is a brownout. ... Due to blackouts (the Philippine term is brownout), especially during the dry season, be prepared with a flashlight and don't forget to save your data in your PC.”