digit

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A human finger or toe.
• noun A corresponding part in other vertebrates.
• noun A unit of length derived from the breadth of a finger and equal to about ³/₄ of an inch (2.0 centimeters).
• noun One of the ten Arabic number symbols, 0 through 9.
• noun Such a symbol used in a system of numeration.
• noun Slang A telephone number.

from The Century Dictionary.

• noun A finger or toe; in the plural, the third segment of the hand (manus) or foot (pes), consisting of the fingers or toes, each of which has usually three, sometimes two, occasionally one, and rarely more than three, joints or phalanges.
• noun A fingerbreadth; a dactyl; one fourth of a palm: a measure of length. The Roman digit was 18.5 millimeters or 0.73 of an English inch. See dactyl and fingerbreadth.
• noun In astronomy, the twelfth part of the diameter of the sun or moon: used in expressing the quantity of an eclipse: as, an eclipse of six digits (one which hides one half of the diameter).
• noun One of the first nine numbers, indicated by the fingers in counting on them; also, one of the nine Arabic numerals, 1, 2, 3, 4, 5, 6, 7, 8, 9.
• To point at or out with the finger.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb rare To point at or out with the finger.
• noun (Zoöl.) One of the terminal divisions of a limb appendage; a finger or toe.
• noun A finger's breadth, commonly estimated to be three fourths of an inch.
• noun (Math.) One of the ten figures or symbols, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, by which all numbers are expressed; -- so called because of the use of the fingers in counting and computing.
• noun (Anat.) One twelfth part of the diameter of the sun or moon; -- a term used to express the quantity of an eclipse.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A finger or toe.
• noun A numeral that can be combined with others to write larger numbers, and that cannot itself be split into other numerals.
• noun slang, UK, in the plural One's phone number.
• verb transitive To point at or point out with the finger.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun one of the elements that collectively form a system of numeration
• noun a finger or toe in human beings or corresponding body part in other vertebrates
• noun the length of breadth of a finger used as a linear measure