digit

Definitions

Economics

• Used in indicating the extent of disaggregation of data within a classification system. For example, 3-digit trade data, categorized by 3-digit numbers, are more aggregated than 6-digit data: many more and hence smaller groups of goods can be categorized with 6-digit numbers.

Electronics

• A symbol used to represent a unit within a numbering system. In the decimal system, the digits are 0 through 9, while in the binary system they are 0 and 1. For example, the number 2004 has four digits. The number of possible digits for any given numbering system is equal to the radix, or base, of the particular system.

Origin & History of “digit”

Digit was borrowed from Latin digitus. this meant ‘finger or toe’, but its underlying etymological sense is probably ‘pointer’; it appears to come from an Indo-European base *deik-, which also produced Latin dicere ‘say’ (originally ‘point out’), Greek deiknúnai ‘show’, Sanskrit diç- ‘show’, and possibly English toe. The word was used in classical times for a measure of length, a ‘finger’s breadth’, but the mathematical sense ‘any of the numbers from 0 to 9’ (originally as counted on the fingers) is a later development.

Digitalis (17th c.), the scientific name of the ‘foxglove’, is a modern Latin use of the Latin adjective digitālis ‘of the finger’, perhaps in allusion to the foxglove’s German name fingerhut ‘thimble’, literally ‘finger-hat’.
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