They're rolled in craps (4)
I believe the answer is:
dice
'they're rolled in craps' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for dice that I've seen before include "Gambling items" , "Numbered cube(s)" , "Gamble; cut into cubes" , "Take a risk" , "Cubes used in gambling" .)