red ink, n. — Green’s Dictionary of Slang

red ink n.

1. as a red liquid.

(a) blood.

1832		Spirit of the Times (NY) 4 Feb. 1/2: Tip him a second edition of Mendoza — let out his red ink.
1855		(con. 1820) Fights for the Championship 61: [He] gave Painter so severe a blow on his right cheek that red ink was the result.
1858		A. Mayhew Paved with Gold 190: He most amiably returned the compliment on Jack’s cheek, ‘peeling the bark,’ setting the ‘red ink’ running.
1909		Aberdeen Jrnl 27 Mar. 3/5: Lady Constance Lytton made some notes with ‘red ink.’ ‘With my blood,’ she said, smiling.
1923		H.C. Witwer Fighting Blood 121: The red ink starts afresh.
1925		J. Tully Beggars of Life 22: He was gently placed against the pillows in a half-sitting position. ‘That might keep the red ink from flowin’ outta his mouth,’ said the scarred-face man.

(b) (US) cheap red wine; thus attrib.

1853		T. Haliburton Sam Slick’s Wise Saws II 282: Drink water in Maine, champaigne in New York [...] and everything in New Orleens, from whiskey down to red-ink – that they call claret.
1899		Hartford Herald (KY) 9 Aug. 1/4: In the East he acquired [...] an unquenchable thirst for bitters, bad whiskey, red ink and other liquids.
1901		J. Hart Argonaut Letters 328: Doubtless many a bookmaker, drinking his noisy pint of champagne with all its pomp and circumstance of effervescence, cracked ice, and wine-cooler, looked with ill-concealed disdain on the quiet persons near him drinking ‘red ink’ out of a bottle without any label.
1908		K. McGaffey Sorrows of a Show Girl Ch. ii: One of those joints where you get everything from soup to nuts, including a scuttle full of red ink for thirty-five scudi.
1912		Sport (Adelaide) 14 Dec. 15/2: They Say [...] That Reggy S. was the worse for red ink after the St Oswald match.
1915		O.O. McIntyre New York Day by Day 30 June [synd. col.] Her dinner price remained the same — 65 cents with a bottle of win [sic] — ‘red ink’ New Yorkers call it — thrown in.
1916		O.O. McIntyre New York Day by Day 25 Sept. [synd. col.] It was in one of the red ink table d’hotes a few steps from Broadway.
1918		E. Wilson ‘Death of a Soldier’ in A Prelude (1967) 192: All this here goddam red ink! It ain’t no good to drink!
1926		J. Black You Can’t Win (2000) 129: The wine dumps, where wine bums or ‘winos’ hung out, interested me. Long, dark, dirty rooms with rows of rickety tables, and a long bar behind which were barrels of the deadly ‘foot juice’ or ‘red ink,’ as the winos called it.
1936		(con. 1920s) Dos Passos Big Money in USA (1966) 785: Say, how about you and me go have a drink of whiskey to take the taste of that damn red ink out of our mouths.
1944		‘F. Bonnamy’ A Rope of Sand (1947) 107: They held hands and drank a half bottle of red ink.

1936

R.F. Adams Cowboy Lingo 228: The Westerner’s names for whiskey were legion [...] ‘red ink’.

2. (orig. US) the debit side of an account; a financial loss [in pre-computing days debts were written in red, credits in black].

1929		Century mag. (NY) Mar. 605/2: Red ink returns were as prolific as asparagus, which meant you [...] dug deep for the freight money .
1938		W. Winchell On Broadway 11 Oct. [synd. col.] One of the Newark newspapers is gasping — too much red ink.
1944		L. Glassop We Were the Rats 79: I got more red ink in me paybook than any joker.

In compounds

red ink corner (n.) [SE red ink represents a loss as entered in accounts]

(US und.) an area of a nightclub reserved for gangsters and policemen, neither of whom paid.

1933

S. Walker Night Club Era 148: [S]itting in the ‘cuff’ or ‘red ink’ corner, a spot reserved for accomplished gangsters, representatives of the law, and a few Broadway columnists who don't feel they should be called upon to pay for their food, drink and entertainment.

red ink joint (n.) [joint n. (3b)]

(US) a cheap Italian restaurant.

1912		Bridgeport Eve. Farmer (CT) 6 Apr. 9/4: In these degenerate days, when the so-called Bohemians [...] meet ina a red-ink joint, they are as staid and solemn as boiled owls.
1917		O.O. McIntyre New York Day by Day 22 Feb. [synd. col.] Six o’clock is the magic trysting hour, whether it is in a red ink table d’hote or Sherry’s.
1925		Black Mask Aug. III 59: Helen and Al had gone to supper at one of the Italian red ink restaurants off Broadway.
1933		S. Walker Night Club Era 82: The hotels began to adopt the table d'hôte, long the symbol of the red-ink joints, which were being driven to the wall.
1942		R. Oliphant ‘Two Girls—Missing’ in Avenger Jul. 🌐 For the fat Italian and his wife who ran this little spaghetti-and-red-ink joint were standing with their backs against the wall, with their eyes popping out of their heads, while a thick-necked man with curly black hair was pointing a revolver at a young woman who was tied in a chair, with her arms behind her back, and her mouth gagged.