"ninth month of the Roman year," late Old English Septembre, from Old French septembre, setembre, and directly from Latin September (also source of Old French Septembre, Spanish Setiembre, Italian Settembre, German September), from septem "seven" (see seven).

So called because it was the original seventh month of the old Roman calendar, which began the year in March; Julian calendar reform (46 B.C.E.) shifted the new year back two months. For -ber suffix, see December. The native names are Old English hærfestmonað ("harvest month"), haligmonað ("holy month"). By late 14c. as figurative of a later stage of life. Related: Septembral; Hawthorne has Septemberish. Septembrian as "belonging to September" is by 1800; earlier it was a noun, "one who believes that our Lord was born in September" (1640s); also see Septembrist.

in astrophysics, 1968, probably with awareness of the notorious Black Hole of Calcutta, incident of June 19, 1756, in which 146 British POWs taken by the Nawab of Bengal after the capture of Fort William were held overnight in a punishment cell of the barracks (meant to hold 4 people) and all but 23 perished.

"discoloration around the eye from injury" c. 1600, from black (adj.) + eye (n.). The figurative sense of "injury to pride, rebuff" is by 1744; that of "bad reputation" is from 1880s.

In reference to dark eyes, often as a mark of beauty, from 1660s. Black-eyed is from 1590s in reference to women, from 1728 in reference to peas. The black-eyed Susan as a flower name (various species) is by 1881, for their appearance. It also was the title of a poem by John Gay (1685-1732), which led to a popular mid-19c. British stage play of the same name.

All in the Downs the fleet was moored,

  The streamers waving in the wind,

When black-eyed Susan came aboard,

  "Oh! where shall I my true love find?

Tell me, ye jovial sailors, tell me true,

If my sweet William sails among the crew?"

[etc.]

1961, "comedy that deals in themes and subjects usually regarded as serious or taboo," from black (adj.), in a figurative sense of "morbid," + comedy. Compare French pièce noire, also comédie noire "macabre or farcical rendering of a violent or tragic theme" (1958, perhaps the inspiration for the English term) and 19th-century gallows-humor. In a racial sense, from 1921.

"friar of the Dominican order," c. 1500, so called from the color of their dress.

pigment or ink made with pure, fine carbon, originally from the soot produced by burning oil in lamps, 1590s, see lamp (n.) + black (n.).

also blackshirt, 1922, member of Fasci di Combattimento, Italian paramilitary unit founded 1919 by Mussolini; so called for their uniforms.