1 [cartography] The ratio or relationship between a distance or area on a map and the corresponding distance or area on the ground, commonly expressed as a fraction or ratio. A map scale of 1/100,000 or 1:100,000 means that one unit of measure on the map equals 100,000 of the same unit on the earth.
2 [data quality] In reference to double precision, the number of digits to the right of the decimal point in a number. For example, the number 56.78 has a scale of 2.