Green’s Dictionary of Slang

playing cards.

1933		C.E. Leach On Top of the Und. in DSUE (1984).
1936		Sunshine Advocate (Vic.) 11 Sept. 6/3: A card sharper belongs to the ‘broad mob,’ and their cards are called ‘dracs’.
1937		J. Curtis You’re in the Racket, Too 244: ‘You’ll play a five-card trick.’ ‘Who’s playing these bleeding duracs, me or you?’.
1946		S. Jackson Indiscreet Guide to Soho 94: They are waiting for a new pack of ‘d’racs’ (cards).
1950		P. Hoskins No Hiding Place! 190/1: D’racs. Cards (back slang).