Green’s Dictionary of Slang

dark n.

1. [mid–late 19C] (Aus.) Australian-distilled, dark, very strong brandy [the dark red colour].

2. [mid-19C+] (US) a derog. term for a black person [abbr. darkie n. (1)/SE dark].

3. [late 19C–1900s] (Aus./US prison) solitary confinement in a dark cell.

4. [1910s] (Aus.) a nickname for those with dark hair or complexion.

5. [1960s] (US campus) a fool, a dullard [dark adj. (1)].

6. [1980s+] (Aus. prison) tobacco [the dark red colour].

In compounds

darktown (n.) (also darkeytown, darkytown) [darkie n. (1)]

[late 19C+] (US) the black area of a town or city; also attrib.

SE in slang uses

In compounds

In phrases

in the dark (adj.) [the colour of the coffee]

[late 19C–1940s] (US) of coffee, black.

late dark (n.)

[1930s–40s] (US black) a very dark night, with neither moon nor stars.