1-A color widely defined as the absence of light.
2-The darkest shade possible
3-The opposite of white, imho, best described on the Yin&Yang symbol.
1-"I see a red door and I want to paint it black"-the_Rolling_Stones.
2-"You should use a black crayon to draw some shade, if your door is open to the night"-Art-Teacher.
3-"the white on the yin&yang symbol is opposite yet complimentary and equal to the black."