noun /ˈdɪdʒɪt/
The digits of the decimal number system are 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9, and those in the hexadecimal number system are those in the decimal system along with A, B, C, D, E and F.
b) A numeral that can be combined with others to write larger numbers, and that cannot itself be split into other numerals.
Wikipedia foundation.