memory loss vs blackout

memory loss and blackout both are nouns.

Word	Noun	Adjective	Verb	Adverb
memory loss	Yes	No	No	No
blackout	Yes	No	No	No

As nouns, memory loss and blackout are synonyms defined as:

Other synonyms of memory loss include amnesia.

memory loss (noun)	blackout (noun)
partial or total loss of memory	a momentary loss of consciousness
	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