Green’s Dictionary of Slang

(US gambling) the point of eight in craps dice.

1915		Cosmopolitan 59 141/1: 1915 ‘Eighter from Decatur!’ shouted the youth[...] ‘A six and a deuce! A five and three! Two bright fours! A nice little eight for all that money! Bones!’ .
1916		Wash. Post 19 Nov. ES5/1: There is a great snapping of fingers, and the men bending over the tables are heard to utter these mysterious cabalistic words: ‘Come on, Little Joe!’ [...] ‘Eighter from Decatur!’.
1920		F.S. Fitzgerald ‘The Jelly Bean’ in Bodley Head Scott Fitzgerald V (1963) 212: Little Ada, this time we’re going South.
1920		Capt. Billy’s Whiz Bang Oct. 24: I indulged in a friendly game of dancing dominoes last night with my old buddy, Mr. ‘Eighter from Decatur.’ ‘Jimmy Hicks’ and ’Long Legged Liz’ were there, but before I got through I had ‘fever in the South’ and ‘crapped’ out.
1921		Truth (Brisbane) 13 Nov. 9/3: Supposing that the player’s ‘point’ is eight, he prays [...] ‘I wants me an eighter. An eighter from decatur’.
1922		(con. 1917–18) S.V. Benét Beginning of Wisdom 220: Ada from Decatur! A five and a three.
1927		Bridgeport (CT) Telegram 21 Nov. 4/5: Nappy makes ebery point on de dice [...] – Little Joe, Feber in de South, Five and a Half, Sixty Days, Two Months and a Half, Eighter From Decatur [etc.].
1935		A.J. Pollock Und. Speaks n.p.: Ada from Decatur, an 8 in craps (dice).
1938		H. Asbury Sucker’s Progress 42: An imbecile has as much chance to win at Craps as the most intelligent of men; he is required only to roll the dice away from him, grunt heavily, and utter one or more of the magic phrases, such as [...] ‘An eighter from Decatur!’.
1949		N. Algren Man with the Golden Arm 11: There it was, Little Joe or Phoebe, Big Dick or Eighter from Decatur, double trey the hard way.
1958		Mad mag. May–June 48: Snake’s point is eight, and he repeatedly shouts ‘Eighter from Decatur!’ as he prepares to roll.
1958		Hughes & Bontemps Book of Negro Folklore 202: 8 – Ada from Decatur.
1962		(con. WWII) J.O. Killens And Then We Heard The Thunder (1964) 448: They found three other MPs shooting dice [...] ‘Ada from Decatur!’ a little sawed-off MP pleaded.
1965		J. Thompson Texas by the Tail (1994) 6: Joe, of course, is the lowest point on the dice. Above it are [...] , Eighter-Decatur [etc.].
1970		D. Ponicsan Last Detail 12: ‘Eighter from Decatur.’ He tosses the dice again and loses, a four and a three.
1996		Eble Sl. and Sociability 50: Ada from Decatur for ‘point eight in craps’ is useful among dice gamblers.
2004		‘Animated Dominoes, Dice’ at Old and Sold 🌐 Some of the best-known nicknames in dice are: [...] Decatur, Ada from Decatur, Eighter from Decatur: total of eight.