dark vs late-night hour

dark and late-night hour both are nouns.

Word	Noun	Adjective	Verb	Adverb
dark	Yes	Yes	No	No
late-night hour	Yes	No	No	No

dark (noun)	late-night hour (noun)
an unenlightened state	the latter part of night
an unilluminated area
absence of light or illumination
absence of moral or spiritual values
the time after sunset and before sunrise while it is dark outside

dark (adjective)	late-night hour (adjective)
devoid of or deficient in light or brightness; shadowed or black
(used of color) having a dark hue
brunet (used of hair or skin or eyes)
secret
causing dejection
stemming from evil characteristics or forces; wicked or dishonorable
showing a brooding ill humor
not giving performances; closed
marked by difficulty of style or expression
lacking enlightenment or knowledge or culture