blackout vs brownout

blackout and brownout both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackout	Yes	No	No	No
brownout	Yes	No	No	No

As nouns, blackout and brownout are synonyms defined as:

blackout and brownout: darkness resulting from the extinction of lights (as in a city invisible to enemy aircraft)

Other synonyms of blackout include dimout.

blackout (noun)	brownout (noun)
a momentary loss of consciousness	darkness resulting from the extinction of lights (as in a city invisible to enemy aircraft)
partial or total loss of memory
the failure of electric power for a general region
darkness resulting from the extinction of lights (as in a city invisible to enemy aircraft)
a suspension of radio or tv broadcasting