n. 1. also called figure. any of the ten Arabic numerals, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, of the decimal system. 2. by analogy, any of the single symbols used to represent the numbers from 0 to b - 1 in counting to the base b. For example, in base 12, the extra digits T and E are used; in base 16, the extra digits are A, B, C, D, E, F.