darkness vs dimout

darkness and dimout both are nouns.

Word	Noun	Adjective	Verb	Adverb
darkness	Yes	No	No	No
dimout	Yes	No	No	No

As nouns, dimout is a hyponym of darkness; that is, dimout is a word with a more specific, narrower meaning than darkness:

darkness: absence of light or illumination
dimout: darkness resulting from the extinction of lights (as in a city invisible to enemy aircraft)

darkness (noun)	dimout (noun)
a swarthy complexion	darkness resulting from the extinction of lights (as in a city invisible to enemy aircraft)
having a dark or somber color
an unenlightened state
an unilluminated area
absence of light or illumination
absence of moral or spiritual values