:bignum: /big'nuhm/ [orig. from MIT MacLISP] n. 1. [techspeak] A multiple-precision computer representation for very large integers. More generally, any very large number. "Have you ever looked at the United States Budget? There's bignums for you!" 2. [Stanford] In backgammon, large numbers on the dice are called `bignums', especially a roll of double fives or double sixes (compare {moby}, sense 4). See also {El Camino Bignum}.