Digit

n. [Lat. digitus, a finger, an inch, the sixteenth part of a Roman foot, akin to Gr. δεικνύναι, to show, point; It. digito, Fr. doigt.]

1. A finger. [Low.]
2. The measure of a finger's breadth, or three fourths of an inch.
3. (Arith.) One of the nine figures or symbols, 1, 2, 3, 4, 5, 6, 7, 8, 9, by which, with the cipher, 0, all numbers are expressed; any number to ten.
4. (Astron.) The twelfth part of the diameter of the sun or moon;—a term used to express the quantity of an eclipse; as, an eclipse of six digits is one which hides one half of the diameter of the disk.