dark

adjective

1
not giving performances; closed
the theater is dark on Mondays
2
having skin rich in melanin pigments
National Association for the Advancement of Colored People
dark-skinned peoples
3
brunet (used of hair or skin or eyes)
dark eyes
4
devoid of or deficient in light or brightness; shadowed or black
sitting in a dark corner
a dark day
5
causing dejection
a blue day
the dark days of the war
6
(used of color) having a dark hue
dark green
dark glasses
7
marked by difficulty of style or expression
much that was dark is now quite clear to me
those who do not appreciate Kafka's work say his style is obscure

1
an unenlightened state
he was in the dark concerning their intentions
his lectures dispelled the darkness
2
an unilluminated area
he moved off into the darkness
3
absence of light or illumination
4
absence of moral or spiritual values
the powers of darkness
5
the time after sunset and before sunrise while it is dark outside

Also useful for “dark”:Scrabble— High-value letters — see what it scores