from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Plural form of boxcar.
- n. Double six in a dice game with two dice.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. (usually plural) an expression used when two dice are thrown and both come up showing six spots
From the resemblance of the six on a die with a boxcar. (Wiktionary)